*************** Case 1 *************** drop database if exists explain_db; { "drop_database_arg":"tenant_id", "database_name":"explain_db", "if_exist":true } *************** Case 2 *************** create database explain_db; { "create_database_arg":"database_schema", "database_id":-1, "schema_version":1, "database_name":"explain_db", "replica_num":0, "zone_list": [ ], "primary_zone":"", "charset_type":2, "collation_type":"utf8mb4_general_ci", "name_case_mode":-1, "comment":"" } *************** Case 3 *************** use explain_db; { "stmt_type":81, "table_items": [ ], "column_items": [ ] } *************** Case 4 *************** create table t1(c1 int primary key, c2 int); { "stmt_type":17, "create_table_arg": { "if_not_exist":false, "schema": { "tenant_id":1, "database_id":1099511628779, "tablegroup_id":1099511627777, "table_id":-1, "table_name":"t1", "max_used_column_id":17, "rowkey_column_num":1, "index_column_num":0, "rowkey_split_pos":0, "block_size":16384, "is_use_bloomfilter":false, "step_merge_num":1, "replica_num":0, "load_type":0, "table_type":0, "index_type":0, "def_type":1, "charset_type":2, "collation_type":45, "data_table_id":0, "create_mem_version":0, "index_status":1, "name_casemode":-1, "code_version":1, "schema_version":0, "last_modified_frozen_version":0, "part_level":1, "part_expr": { "part_func_type":0, "part_func_expr":"", "part_num":1 }, "comment":"", "tablegroup_name":"", "compress_func_name":"none", "primary_zone":"", "expire_info":"", "view_schema": { "view_definition":"", "check_option":"none", "is_updatable":"false", "alias_name":"" }, "autoinc_column_id":0, "auto_increment":0, "index_tid_array": [ ], "column_array": [ { "tenant_id":-1, "table_id":-1, "column_id":16, "schema_version":0, "rowkey_position":1, "index_position":0, "order_in_rowkey":0, "meta_type": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "is_nullable":false, "is_zero_fill":false, "is_autoincrement":false, "is_hidden":false, "charset_type":2, "on_update_current_timestamp":false, "orig_default_value": { "NULL":"NULL" }, "cur_default_value": { "NULL":"NULL" }, "column_name":"c1", "comment":"" }, { "tenant_id":-1, "table_id":-1, "column_id":17, "schema_version":0, "rowkey_position":0, "index_position":0, "order_in_rowkey":0, "meta_type": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "is_nullable":true, "is_zero_fill":false, "is_autoincrement":false, "is_hidden":false, "charset_type":2, "on_update_current_timestamp":false, "orig_default_value": { "NULL":"NULL" }, "cur_default_value": { "NULL":"NULL" }, "column_name":"c2", "comment":"" } ] }, "index_arg_list": [ ] }, "db_name":"explain_db" } *************** Case 5 *************** create table t2(c1 int primary key, c2 int, c3 varchar(32)); { "stmt_type":17, "create_table_arg": { "if_not_exist":false, "schema": { "tenant_id":1, "database_id":1099511628779, "tablegroup_id":1099511627777, "table_id":-1, "table_name":"t2", "max_used_column_id":18, "rowkey_column_num":1, "index_column_num":0, "rowkey_split_pos":0, "block_size":16384, "is_use_bloomfilter":false, "step_merge_num":1, "replica_num":0, "load_type":0, "table_type":0, "index_type":0, "def_type":1, "charset_type":2, "collation_type":45, "data_table_id":0, "create_mem_version":0, "index_status":1, "name_casemode":-1, "code_version":1, "schema_version":0, "last_modified_frozen_version":0, "part_level":1, "part_expr": { "part_func_type":0, "part_func_expr":"", "part_num":1 }, "comment":"", "tablegroup_name":"", "compress_func_name":"none", "primary_zone":"", "expire_info":"", "view_schema": { "view_definition":"", "check_option":"none", "is_updatable":"false", "alias_name":"" }, "autoinc_column_id":0, "auto_increment":0, "index_tid_array": [ ], "column_array": [ { "tenant_id":-1, "table_id":-1, "column_id":16, "schema_version":0, "rowkey_position":1, "index_position":0, "order_in_rowkey":0, "meta_type": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "is_nullable":false, "is_zero_fill":false, "is_autoincrement":false, "is_hidden":false, "charset_type":2, "on_update_current_timestamp":false, "orig_default_value": { "NULL":"NULL" }, "cur_default_value": { "NULL":"NULL" }, "column_name":"c1", "comment":"" }, { "tenant_id":-1, "table_id":-1, "column_id":17, "schema_version":0, "rowkey_position":0, "index_position":0, "order_in_rowkey":0, "meta_type": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "is_nullable":true, "is_zero_fill":false, "is_autoincrement":false, "is_hidden":false, "charset_type":2, "on_update_current_timestamp":false, "orig_default_value": { "NULL":"NULL" }, "cur_default_value": { "NULL":"NULL" }, "column_name":"c2", "comment":"" }, { "tenant_id":-1, "table_id":-1, "column_id":18, "schema_version":0, "rowkey_position":0, "index_position":0, "order_in_rowkey":0, "meta_type": { "type":"VARCHAR", "collation":"utf8mb4_general_ci", "coercibility":"IGNORABLE" }, "accuracy": { "length":32, "precision":32, "scale":0 }, "is_nullable":true, "is_zero_fill":false, "is_autoincrement":false, "is_hidden":false, "charset_type":2, "on_update_current_timestamp":false, "orig_default_value": { "NULL":"NULL" }, "cur_default_value": { "NULL":"NULL" }, "column_name":"c3", "comment":"" } ] }, "index_arg_list": [ ] }, "db_name":"explain_db" } *************** Case 6 *************** explain select 1; { "explain_stmt": { "stmt_type":1, "table": [ ], "joined_table": [ ], "partition_express": [ ], "column": [ ], "select": [ { "expression": { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":1 } }, "table_id":-1, "column_id":65519, "is_alias":false, "alias_name":"1", "expr_name":"1", "obj_type":"BIGINT", "length":65535, "precision":-1, "scale":0, "default": { "NULL":"NULL" }, "nullable":true } ], "distinct":false, "from": [ ], "where": [ ], "group_by": [ ], "having": [ ], "aggr_func": [ ], "order_by": [ ], "limit":null, "offset":null, "for_update":false, "wait":-1, "show_stmt_ctx": { "is_from_show_stmt":false, "global_scope":false, "tenant_id":-1, "show_database_id":-1, "show_table_id":-1, "grants_user_id":-1 }, "when": [ ], "hint": { "read_static":false, "frozen_version":-1, "topk_precision":-1, "sharding_minimum_row_count":0, "query_timeout":-1, "hotspot":false, "index": [ ], "read_consistency":0, "join_ordered":false, "join_order": [ ], "merge_hint_ids": [ ], "hash_hint_ids": [ ], "nl_hint_ids": [ ], "part_hints": [ ] }, "query_context": { "param_num":0, "fetch_cur_time":true, "calculable_items": [ ] }, "current_level":0, "equal_sets": [ ], "child_stmts": [ ] } } *************** Case 7 *************** explain select 1+1; { "explain_stmt": { "stmt_type":1, "table": [ ], "joined_table": [ ], "partition_express": [ ], "column": [ ], "select": [ { "expression": { "item_type":"T_QUESTIONMARK", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "IS_STATIC_PARAM", "IS_CALCULABLE_EXPR", "IS_CONST_EXPR", "CNT_CONST", "CNT_STATIC_PARAM", "CNT_CALCULABLE_EXPR" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "UNKNOWN":0 } }, "table_id":-1, "column_id":65519, "is_alias":false, "alias_name":"1+1", "expr_name":"1+1", "obj_type":"BIGINT", "length":65535, "precision":-1, "scale":0, "default": { "NULL":"NULL" }, "nullable":true } ], "distinct":false, "from": [ ], "where": [ ], "group_by": [ ], "having": [ ], "aggr_func": [ ], "order_by": [ ], "limit":null, "offset":null, "for_update":false, "wait":-1, "show_stmt_ctx": { "is_from_show_stmt":false, "global_scope":false, "tenant_id":-1, "show_database_id":-1, "show_table_id":-1, "grants_user_id":-1 }, "when": [ ], "hint": { "read_static":false, "frozen_version":-1, "topk_precision":-1, "sharding_minimum_row_count":0, "query_timeout":-1, "hotspot":false, "index": [ ], "read_consistency":0, "join_ordered":false, "join_order": [ ], "merge_hint_ids": [ ], "hash_hint_ids": [ ], "nl_hint_ids": [ ], "part_hints": [ ] }, "query_context": { "param_num":1, "fetch_cur_time":true, "calculable_items": [ { "expression": { "item_type":"T_OP_ADD", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CALCULABLE_EXPR", "IS_CONST_EXPR", "CNT_CONST", "CNT_CALCULABLE_EXPR" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "children": [ { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":1 } }, { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":1 } } ] }, "idx":0 } ] }, "current_level":0, "equal_sets": [ ], "child_stmts": [ ] } } *************** Case 8 *************** explain insert into t1 (c1,c2) values(1,1); { "explain_stmt": { "stmt_type":2, "table": [ { "table_id":1099511630877, "table_name":"t1", "alias_name":"", "table_type":0, "ref_id":1099511630877, "database_name":"explain_db" } ], "partition_express": [ ], "column": [ { "column_id":16, "column_name":"c1", "table_id":1099511630877, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":false, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":16, "expr_level":0 } }, { "column_id":17, "column_name":"c2", "table_id":1099511630877, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":true, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":17, "expr_level":0 } } ], "value": [ { "item_type":"T_FUN_COLUMN_CONV", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "IS_FUNC", "IS_CALCULABLE_EXPR", "IS_CONST_EXPR", "CNT_CONST", "CNT_FUNC", "CNT_CALCULABLE_EXPR" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "func":"column_conv", "children": [ { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":4 } }, { "item_type":"T_INT", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "INT":11 } }, { "item_type":"T_BOOL", "result_type": { "meta": { "type":"TINYINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "TINYINT":0 } }, { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":1 } } ] }, { "item_type":"T_FUN_COLUMN_CONV", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "IS_FUNC", "IS_CALCULABLE_EXPR", "IS_CONST_EXPR", "CNT_CONST", "CNT_FUNC", "CNT_CALCULABLE_EXPR" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "func":"column_conv", "children": [ { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":4 } }, { "item_type":"T_INT", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "INT":11 } }, { "item_type":"T_BOOL", "result_type": { "meta": { "type":"TINYINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "TINYINT":1 } }, { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":1 } } ] } ], "hint": { "read_static":false, "frozen_version":-1, "topk_precision":-1, "sharding_minimum_row_count":0, "query_timeout":-1, "hotspot":false, "index": [ ], "read_consistency":0, "join_ordered":false, "join_order": [ ], "merge_hint_ids": [ ], "hash_hint_ids": [ ], "nl_hint_ids": [ ], "part_hints": [ ] }, "query_context": { "param_num":0, "fetch_cur_time":true, "calculable_items": [ ] } } } *************** Case 9 *************** explain insert into t2 (c1,c2,c3) values(1,1,'a'); { "explain_stmt": { "stmt_type":2, "table": [ { "table_id":1099511630878, "table_name":"t2", "alias_name":"", "table_type":0, "ref_id":1099511630878, "database_name":"explain_db" } ], "partition_express": [ ], "column": [ { "column_id":16, "column_name":"c1", "table_id":1099511630878, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":false, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630878, "column_id":16, "expr_level":0 } }, { "column_id":17, "column_name":"c2", "table_id":1099511630878, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":true, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630878, "column_id":17, "expr_level":0 } }, { "column_id":18, "column_name":"c3", "table_id":1099511630878, "obj_type":"VARCHAR", "length":32, "precision":32, "scale":0, "is_autoincrement":false, "cs_type":"utf8mb4_general_ci", "cs_level":2, "is_nullable":true, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"VARCHAR", "collation":"utf8mb4_general_ci", "coercibility":"IMPLICIT" }, "accuracy": { "length":32, "precision":32, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 2 ], "alias_column_id": [ ], "table_id":1099511630878, "column_id":18, "expr_level":0 } } ], "value": [ { "item_type":"T_FUN_COLUMN_CONV", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "IS_FUNC", "IS_CALCULABLE_EXPR", "IS_CONST_EXPR", "CNT_CONST", "CNT_FUNC", "CNT_CALCULABLE_EXPR" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "func":"column_conv", "children": [ { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":4 } }, { "item_type":"T_INT", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "INT":11 } }, { "item_type":"T_BOOL", "result_type": { "meta": { "type":"TINYINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "TINYINT":0 } }, { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":1 } } ] }, { "item_type":"T_FUN_COLUMN_CONV", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "IS_FUNC", "IS_CALCULABLE_EXPR", "IS_CONST_EXPR", "CNT_CONST", "CNT_FUNC", "CNT_CALCULABLE_EXPR" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "func":"column_conv", "children": [ { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":4 } }, { "item_type":"T_INT", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "INT":11 } }, { "item_type":"T_BOOL", "result_type": { "meta": { "type":"TINYINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "TINYINT":1 } }, { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":1 } } ] }, { "item_type":"T_FUN_COLUMN_CONV", "result_type": { "meta": { "type":"BIGINT", "collation":"utf8mb4_general_ci", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "IS_FUNC", "IS_CALCULABLE_EXPR", "IS_CONST_EXPR", "CNT_CONST", "CNT_FUNC", "CNT_CALCULABLE_EXPR" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "func":"column_conv", "children": [ { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"utf8mb4_general_ci", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":22 } }, { "item_type":"T_INT", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "INT":32 } }, { "item_type":"T_BOOL", "result_type": { "meta": { "type":"TINYINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "TINYINT":1 } }, { "item_type":"T_VARCHAR", "result_type": { "meta": { "type":"VARCHAR", "collation":"utf8mb4_general_ci", "coercibility":"COERCIBLE" }, "accuracy": { "length":1, "precision":1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "VARCHAR":"a", "collation":"utf8mb4_general_ci" } } ] } ], "hint": { "read_static":false, "frozen_version":-1, "topk_precision":-1, "sharding_minimum_row_count":0, "query_timeout":-1, "hotspot":false, "index": [ ], "read_consistency":0, "join_ordered":false, "join_order": [ ], "merge_hint_ids": [ ], "hash_hint_ids": [ ], "nl_hint_ids": [ ], "part_hints": [ ] }, "query_context": { "param_num":0, "fetch_cur_time":true, "calculable_items": [ ] } } } *************** Case 10 *************** explain replace into t1 (c1,c2) values(2,2); { "explain_stmt": { "stmt_type":3, "table": [ { "table_id":1099511630877, "table_name":"t1", "alias_name":"", "table_type":0, "ref_id":1099511630877, "database_name":"explain_db" } ], "partition_express": [ ], "column": [ { "column_id":16, "column_name":"c1", "table_id":1099511630877, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":false, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":16, "expr_level":0 } }, { "column_id":17, "column_name":"c2", "table_id":1099511630877, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":true, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":17, "expr_level":0 } } ], "value": [ { "item_type":"T_FUN_COLUMN_CONV", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "IS_FUNC", "IS_CALCULABLE_EXPR", "IS_CONST_EXPR", "CNT_CONST", "CNT_FUNC", "CNT_CALCULABLE_EXPR" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "func":"column_conv", "children": [ { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":4 } }, { "item_type":"T_INT", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "INT":11 } }, { "item_type":"T_BOOL", "result_type": { "meta": { "type":"TINYINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "TINYINT":0 } }, { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":2 } } ] }, { "item_type":"T_FUN_COLUMN_CONV", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "IS_FUNC", "IS_CALCULABLE_EXPR", "IS_CONST_EXPR", "CNT_CONST", "CNT_FUNC", "CNT_CALCULABLE_EXPR" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "func":"column_conv", "children": [ { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":4 } }, { "item_type":"T_INT", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "INT":11 } }, { "item_type":"T_BOOL", "result_type": { "meta": { "type":"TINYINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "TINYINT":1 } }, { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":2 } } ] } ], "hint": { "read_static":false, "frozen_version":-1, "topk_precision":-1, "sharding_minimum_row_count":0, "query_timeout":-1, "hotspot":false, "index": [ ], "read_consistency":0, "join_ordered":false, "join_order": [ ], "merge_hint_ids": [ ], "hash_hint_ids": [ ], "nl_hint_ids": [ ], "part_hints": [ ] }, "query_context": { "param_num":0, "fetch_cur_time":true, "calculable_items": [ ] } } } *************** Case 11 *************** explain replace into t2 (c1,c2,c3) values(2,2,'b'); { "explain_stmt": { "stmt_type":3, "table": [ { "table_id":1099511630878, "table_name":"t2", "alias_name":"", "table_type":0, "ref_id":1099511630878, "database_name":"explain_db" } ], "partition_express": [ ], "column": [ { "column_id":16, "column_name":"c1", "table_id":1099511630878, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":false, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630878, "column_id":16, "expr_level":0 } }, { "column_id":17, "column_name":"c2", "table_id":1099511630878, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":true, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630878, "column_id":17, "expr_level":0 } }, { "column_id":18, "column_name":"c3", "table_id":1099511630878, "obj_type":"VARCHAR", "length":32, "precision":32, "scale":0, "is_autoincrement":false, "cs_type":"utf8mb4_general_ci", "cs_level":2, "is_nullable":true, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"VARCHAR", "collation":"utf8mb4_general_ci", "coercibility":"IMPLICIT" }, "accuracy": { "length":32, "precision":32, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 2 ], "alias_column_id": [ ], "table_id":1099511630878, "column_id":18, "expr_level":0 } } ], "value": [ { "item_type":"T_FUN_COLUMN_CONV", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "IS_FUNC", "IS_CALCULABLE_EXPR", "IS_CONST_EXPR", "CNT_CONST", "CNT_FUNC", "CNT_CALCULABLE_EXPR" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "func":"column_conv", "children": [ { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":4 } }, { "item_type":"T_INT", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "INT":11 } }, { "item_type":"T_BOOL", "result_type": { "meta": { "type":"TINYINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "TINYINT":0 } }, { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":2 } } ] }, { "item_type":"T_FUN_COLUMN_CONV", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "IS_FUNC", "IS_CALCULABLE_EXPR", "IS_CONST_EXPR", "CNT_CONST", "CNT_FUNC", "CNT_CALCULABLE_EXPR" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "func":"column_conv", "children": [ { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":4 } }, { "item_type":"T_INT", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "INT":11 } }, { "item_type":"T_BOOL", "result_type": { "meta": { "type":"TINYINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "TINYINT":1 } }, { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":2 } } ] }, { "item_type":"T_FUN_COLUMN_CONV", "result_type": { "meta": { "type":"BIGINT", "collation":"utf8mb4_general_ci", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "IS_FUNC", "IS_CALCULABLE_EXPR", "IS_CONST_EXPR", "CNT_CONST", "CNT_FUNC", "CNT_CALCULABLE_EXPR" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "func":"column_conv", "children": [ { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"utf8mb4_general_ci", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":22 } }, { "item_type":"T_INT", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "INT":32 } }, { "item_type":"T_BOOL", "result_type": { "meta": { "type":"TINYINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "TINYINT":1 } }, { "item_type":"T_VARCHAR", "result_type": { "meta": { "type":"VARCHAR", "collation":"utf8mb4_general_ci", "coercibility":"COERCIBLE" }, "accuracy": { "length":1, "precision":1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "VARCHAR":"b", "collation":"utf8mb4_general_ci" } } ] } ], "hint": { "read_static":false, "frozen_version":-1, "topk_precision":-1, "sharding_minimum_row_count":0, "query_timeout":-1, "hotspot":false, "index": [ ], "read_consistency":0, "join_ordered":false, "join_order": [ ], "merge_hint_ids": [ ], "hash_hint_ids": [ ], "nl_hint_ids": [ ], "part_hints": [ ] }, "query_context": { "param_num":0, "fetch_cur_time":true, "calculable_items": [ ] } } } *************** Case 12 *************** explain select c1,c2 from t1 where c1 = 2 and c2 =1 limit 1; { "explain_stmt": { "stmt_type":1, "table": [ { "table_id":1099511630877, "table_name":"t1", "alias_name":"", "table_type":0, "ref_id":1099511630877, "database_name":"explain_db" } ], "joined_table": [ ], "partition_express": [ ], "column": [ { "column_id":16, "column_name":"c1", "table_id":1099511630877, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":false, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":16, "expr_level":0 } }, { "column_id":17, "column_name":"c2", "table_id":1099511630877, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":true, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":17, "expr_level":0 } } ], "select": [ { "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":16, "expr_level":0 }, "table_id":-1, "column_id":65519, "is_alias":false, "alias_name":"c1", "expr_name":"c1", "obj_type":"INT", "length":11, "precision":11, "scale":0, "default": { "NULL":"NULL" }, "nullable":false }, { "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":17, "expr_level":0 }, "table_id":-1, "column_id":65518, "is_alias":false, "alias_name":"c2", "expr_name":"c2", "obj_type":"INT", "length":11, "precision":11, "scale":0, "default": { "NULL":"NULL" }, "nullable":true } ], "distinct":false, "from": [ { "table_id":1099511630877, "is_join":false } ], "where": [ { "item_type":"T_OP_EQ", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":1 }, "expr_info": [ "CNT_CONST", "CNT_COLUMN", "IS_SIMPLE_COND" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "children": [ { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":16, "expr_level":0 }, { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":2 } } ] }, { "item_type":"T_OP_EQ", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "CNT_CONST", "CNT_COLUMN", "IS_SIMPLE_COND" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "children": [ { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":17, "expr_level":0 }, { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":1 } } ] } ], "group_by": [ ], "having": [ ], "aggr_func": [ ], "order_by": [ ], "limit": { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":1 } }, "offset":null, "for_update":false, "wait":-1, "show_stmt_ctx": { "is_from_show_stmt":false, "global_scope":false, "tenant_id":-1, "show_database_id":-1, "show_table_id":-1, "grants_user_id":-1 }, "when": [ ], "hint": { "read_static":false, "frozen_version":-1, "topk_precision":-1, "sharding_minimum_row_count":0, "query_timeout":-1, "hotspot":false, "index": [ ], "read_consistency":0, "join_ordered":false, "join_order": [ ], "merge_hint_ids": [ ], "hash_hint_ids": [ ], "nl_hint_ids": [ ], "part_hints": [ ] }, "query_context": { "param_num":0, "fetch_cur_time":true, "calculable_items": [ ] }, "current_level":0, "equal_sets": [ [ { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":16, "expr_level":0 }, { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":2 } } ], [ { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":17, "expr_level":0 }, { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":1 } } ] ], "child_stmts": [ ] } } *************** Case 13 *************** explain select c1 + c2 from t1; { "explain_stmt": { "stmt_type":1, "table": [ { "table_id":1099511630877, "table_name":"t1", "alias_name":"", "table_type":0, "ref_id":1099511630877, "database_name":"explain_db" } ], "joined_table": [ ], "partition_express": [ ], "column": [ { "column_id":16, "column_name":"c1", "table_id":1099511630877, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":false, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":16, "expr_level":0 } }, { "column_id":17, "column_name":"c2", "table_id":1099511630877, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":true, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":17, "expr_level":0 } } ], "select": [ { "expression": { "item_type":"T_OP_ADD", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":0 }, "expr_info": [ "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0, 1 ], "alias_column_id": [ ], "children": [ { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":16, "expr_level":0 }, { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":17, "expr_level":0 } ] }, "table_id":-1, "column_id":65519, "is_alias":false, "alias_name":"c1 + c2", "expr_name":"c1 + c2", "obj_type":"BIGINT", "length":65535, "precision":-1, "scale":0, "default": { "NULL":"NULL" }, "nullable":true } ], "distinct":false, "from": [ { "table_id":1099511630877, "is_join":false } ], "where": [ ], "group_by": [ ], "having": [ ], "aggr_func": [ ], "order_by": [ ], "limit":null, "offset":null, "for_update":false, "wait":-1, "show_stmt_ctx": { "is_from_show_stmt":false, "global_scope":false, "tenant_id":-1, "show_database_id":-1, "show_table_id":-1, "grants_user_id":-1 }, "when": [ ], "hint": { "read_static":false, "frozen_version":-1, "topk_precision":-1, "sharding_minimum_row_count":0, "query_timeout":-1, "hotspot":false, "index": [ ], "read_consistency":0, "join_ordered":false, "join_order": [ ], "merge_hint_ids": [ ], "hash_hint_ids": [ ], "nl_hint_ids": [ ], "part_hints": [ ] }, "query_context": { "param_num":0, "fetch_cur_time":true, "calculable_items": [ ] }, "current_level":0, "equal_sets": [ ], "child_stmts": [ ] } } *************** Case 14 *************** explain select distinct * from t1; { "explain_stmt": { "stmt_type":1, "table": [ { "table_id":1099511630877, "table_name":"t1", "alias_name":"", "table_type":0, "ref_id":1099511630877, "database_name":"explain_db" } ], "joined_table": [ ], "partition_express": [ ], "column": [ { "column_id":16, "column_name":"c1", "table_id":1099511630877, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":false, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":16, "expr_level":0 } }, { "column_id":17, "column_name":"c2", "table_id":1099511630877, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":true, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":17, "expr_level":0 } } ], "select": [ { "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":16, "expr_level":0 }, "table_id":-1, "column_id":65519, "is_alias":false, "alias_name":"c1", "expr_name":"c1", "obj_type":"INT", "length":11, "precision":11, "scale":0, "default": { "NULL":"NULL" }, "nullable":true }, { "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":17, "expr_level":0 }, "table_id":-1, "column_id":65518, "is_alias":false, "alias_name":"c2", "expr_name":"c2", "obj_type":"INT", "length":11, "precision":11, "scale":0, "default": { "NULL":"NULL" }, "nullable":true } ], "distinct":true, "from": [ { "table_id":1099511630877, "is_join":false } ], "where": [ ], "group_by": [ ], "having": [ ], "aggr_func": [ ], "order_by": [ ], "limit":null, "offset":null, "for_update":false, "wait":-1, "show_stmt_ctx": { "is_from_show_stmt":false, "global_scope":false, "tenant_id":-1, "show_database_id":-1, "show_table_id":-1, "grants_user_id":-1 }, "when": [ ], "hint": { "read_static":false, "frozen_version":-1, "topk_precision":-1, "sharding_minimum_row_count":0, "query_timeout":-1, "hotspot":false, "index": [ ], "read_consistency":0, "join_ordered":false, "join_order": [ ], "merge_hint_ids": [ ], "hash_hint_ids": [ ], "nl_hint_ids": [ ], "part_hints": [ ] }, "query_context": { "param_num":0, "fetch_cur_time":true, "calculable_items": [ ] }, "current_level":0, "equal_sets": [ ], "child_stmts": [ ] } } *************** Case 15 *************** explain select c1, sum(c2) from t1 where c1 > 0 and c2 + c1 = 100 group by c2 order by c1 desc limit 0, 1; { "explain_stmt": { "stmt_type":1, "table": [ { "table_id":1099511630877, "table_name":"t1", "alias_name":"", "table_type":0, "ref_id":1099511630877, "database_name":"explain_db" } ], "joined_table": [ ], "partition_express": [ ], "column": [ { "column_id":16, "column_name":"c1", "table_id":1099511630877, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":false, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":16, "expr_level":0 } }, { "column_id":17, "column_name":"c2", "table_id":1099511630877, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":true, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":17, "expr_level":0 } } ], "select": [ { "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":16, "expr_level":0 }, "table_id":-1, "column_id":65519, "is_alias":false, "alias_name":"c1", "expr_name":"c1", "obj_type":"INT", "length":11, "precision":11, "scale":0, "default": { "NULL":"NULL" }, "nullable":false }, { "expression": { "item_type":"T_FUN_SUM", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_AGG", "CNT_COLUMN", "CNT_AGG" ], "rel_id": [ 1 ], "base_column_id": [ ], "alias_column_id": [ ], "children": [ { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":17, "expr_level":0 } ], "distinct":false, "order_by": [ ], "separator_param_idx":-1 }, "table_id":-1, "column_id":65508, "is_alias":false, "alias_name":"sum(c2)", "expr_name":"sum(c2)", "obj_type":"BIGINT", "length":11, "precision":11, "scale":0, "default": { "NULL":"NULL" }, "nullable":true } ], "distinct":false, "from": [ { "table_id":1099511630877, "is_join":false } ], "where": [ { "item_type":"T_OP_GT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":1 }, "expr_info": [ "CNT_CONST", "CNT_COLUMN", "IS_RANGE_COND" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "children": [ { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":16, "expr_level":0 }, { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":0 } } ] }, { "item_type":"T_OP_EQ", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "CNT_CONST", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0, 1 ], "alias_column_id": [ ], "children": [ { "item_type":"T_OP_ADD", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":0 }, "expr_info": [ "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0, 1 ], "alias_column_id": [ ], "children": [ { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":17, "expr_level":0 }, { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":16, "expr_level":0 } ] }, { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":100 } } ] } ], "group_by": [ { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":17, "expr_level":0 } ], "having": [ ], "aggr_func": [ { "column_id":65518, "expression": { "item_type":"T_FUN_SUM", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_AGG", "CNT_COLUMN", "CNT_AGG" ], "rel_id": [ 1 ], "base_column_id": [ ], "alias_column_id": [ ], "children": [ { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":17, "expr_level":0 } ], "distinct":false, "order_by": [ ], "separator_param_idx":-1 } } ], "order_by": [ { "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":16, "expr_level":0 }, "ascending":"DESC" } ], "limit": { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":1 } }, "offset": { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":0 } }, "for_update":false, "wait":-1, "show_stmt_ctx": { "is_from_show_stmt":false, "global_scope":false, "tenant_id":-1, "show_database_id":-1, "show_table_id":-1, "grants_user_id":-1 }, "when": [ ], "hint": { "read_static":false, "frozen_version":-1, "topk_precision":-1, "sharding_minimum_row_count":0, "query_timeout":-1, "hotspot":false, "index": [ ], "read_consistency":0, "join_ordered":false, "join_order": [ ], "merge_hint_ids": [ ], "hash_hint_ids": [ ], "nl_hint_ids": [ ], "part_hints": [ ] }, "query_context": { "param_num":0, "fetch_cur_time":true, "calculable_items": [ ] }, "current_level":0, "equal_sets": [ [ { "item_type":"T_OP_ADD", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":0 }, "expr_info": [ "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0, 1 ], "alias_column_id": [ ], "children": [ { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":17, "expr_level":0 }, { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":16, "expr_level":0 } ] }, { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":100 } } ] ], "child_stmts": [ ] } } *************** Case 16 *************** explain select c1 as tc1 from t1 union select c2 from t2; { "explain_stmt": { "set_op":1, "distinct":true, "left_query": { "stmt_type":1, "table": [ { "table_id":1099511630877, "table_name":"t1", "alias_name":"", "table_type":0, "ref_id":1099511630877, "database_name":"explain_db" } ], "joined_table": [ ], "partition_express": [ ], "column": [ { "column_id":16, "column_name":"c1", "table_id":1099511630877, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":false, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":16, "expr_level":0 } } ], "select": [ { "expression": { "item_type":"T_FUN_SYS_ALIAS_REF", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_FUNC", "CNT_COLUMN", "CNT_FUNC" ], "rel_id": [ 1 ], "base_column_id": [ ], "alias_column_id": [ 0 ], "func":"tc1", "children": [ { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":16, "expr_level":0 } ] }, "table_id":-1, "column_id":65519, "is_alias":true, "alias_name":"tc1", "expr_name":"c1", "obj_type":"INT", "length":11, "precision":11, "scale":0, "default": { "NULL":"NULL" }, "nullable":false } ], "distinct":false, "from": [ { "table_id":1099511630877, "is_join":false } ], "where": [ ], "group_by": [ ], "having": [ ], "aggr_func": [ ], "order_by": [ ], "limit":null, "offset":null, "for_update":false, "wait":-1, "show_stmt_ctx": { "is_from_show_stmt":false, "global_scope":false, "tenant_id":-1, "show_database_id":-1, "show_table_id":-1, "grants_user_id":-1 }, "when": [ ], "hint": { "read_static":false, "frozen_version":-1, "topk_precision":-1, "sharding_minimum_row_count":0, "query_timeout":-1, "hotspot":false, "index": [ ], "read_consistency":0, "join_ordered":false, "join_order": [ ], "merge_hint_ids": [ ], "hash_hint_ids": [ ], "nl_hint_ids": [ ], "part_hints": [ ] }, "query_context": { "param_num":0, "fetch_cur_time":true, "calculable_items": [ ] }, "current_level":0, "equal_sets": [ ], "child_stmts": [ ] }, "right_query": { "stmt_type":1, "table": [ { "table_id":1099511630878, "table_name":"t2", "alias_name":"", "table_type":0, "ref_id":1099511630878, "database_name":"explain_db" } ], "joined_table": [ ], "partition_express": [ ], "column": [ { "column_id":17, "column_name":"c2", "table_id":1099511630878, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":true, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630878, "column_id":17, "expr_level":0 } } ], "select": [ { "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630878, "column_id":17, "expr_level":0 }, "table_id":-1, "column_id":65518, "is_alias":false, "alias_name":"c2", "expr_name":"c2", "obj_type":"INT", "length":11, "precision":11, "scale":0, "default": { "NULL":"NULL" }, "nullable":true } ], "distinct":false, "from": [ { "table_id":1099511630878, "is_join":false } ], "where": [ ], "group_by": [ ], "having": [ ], "aggr_func": [ ], "order_by": [ ], "limit":null, "offset":null, "for_update":false, "wait":-1, "show_stmt_ctx": { "is_from_show_stmt":false, "global_scope":false, "tenant_id":-1, "show_database_id":-1, "show_table_id":-1, "grants_user_id":-1 }, "when": [ ], "hint": { "read_static":false, "frozen_version":-1, "topk_precision":-1, "sharding_minimum_row_count":0, "query_timeout":-1, "hotspot":false, "index": [ ], "read_consistency":0, "join_ordered":false, "join_order": [ ], "merge_hint_ids": [ ], "hash_hint_ids": [ ], "nl_hint_ids": [ ], "part_hints": [ ] }, "query_context": { "param_num":0, "fetch_cur_time":true, "calculable_items": [ ] }, "current_level":0, "equal_sets": [ ], "child_stmts": [ ] }, "order_by": [ ], "limit":null, "select": [ { "expression": { "item_type":"T_FUN_SYS_ALIAS_REF", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_FUNC", "CNT_COLUMN", "CNT_FUNC" ], "rel_id": [ 1 ], "base_column_id": [ ], "alias_column_id": [ 0 ], "func":"tc1", "children": [ { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":16, "expr_level":0 } ] }, "table_id":-1, "column_id":65519, "is_alias":false, "alias_name":"tc1", "expr_name":"c1", "obj_type":"INT", "length":-1, "precision":-1, "scale":-1, "default": { "NULL":"NULL" }, "nullable":false } ] } } *************** Case 17 *************** explain update t1 set c1 = 3 where c2 =1; { "explain_stmt": { "stmt_type":5, "table": [ { "table_id":1099511630877, "table_name":"t1", "alias_name":"", "table_type":0, "ref_id":1099511630877, "database_name":"explain_db" } ], "partition_express": [ ], "column": [ { "column_id":16, "column_name":"c1", "table_id":1099511630877, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":false, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":16, "expr_level":0 } }, { "column_id":17, "column_name":"c2", "table_id":1099511630877, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":false, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":17, "expr_level":0 } } ], "input_columns": [ { "table_id":1099511630877, "table_name":"t1", "column": [ { "column_id":16, "column_name":"c1", "table_id":1099511630877, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":false, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":16, "expr_level":0 } }, { "column_id":17, "column_name":"c2", "table_id":1099511630877, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":false, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":17, "expr_level":0 } } ] } ], "assign": [ { "table": { "table_id":1099511630877, "table_name":"t1", "alias_name":"", "table_type":0, "ref_id":1099511630877, "database_name":"explain_db" }, "assign": [ { "column": { "column_id":16, "column_name":"c1", "table_id":1099511630877, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":false, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":16, "expr_level":0 } }, "expression": { "item_type":"T_FUN_COLUMN_CONV", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "IS_FUNC", "IS_CALCULABLE_EXPR", "IS_CONST_EXPR", "CNT_CONST", "CNT_FUNC", "CNT_CALCULABLE_EXPR" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "func":"column_conv", "children": [ { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":4 } }, { "item_type":"T_INT", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "INT":11 } }, { "item_type":"T_BOOL", "result_type": { "meta": { "type":"TINYINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "TINYINT":0 } }, { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":3 } } ] } } ] } ], "where": [ { "item_type":"T_OP_EQ", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":1 }, "expr_info": [ "CNT_CONST", "CNT_COLUMN", "IS_SIMPLE_COND" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "children": [ { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":17, "expr_level":0 }, { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":1 } } ] } ], "order_by": [ ], "limit":null, "offset":null, "hint": { "read_static":false, "frozen_version":-1, "topk_precision":-1, "sharding_minimum_row_count":0, "query_timeout":-1, "hotspot":false, "index": [ ], "read_consistency":0, "join_ordered":false, "join_order": [ ], "merge_hint_ids": [ ], "hash_hint_ids": [ ], "nl_hint_ids": [ ], "part_hints": [ ] }, "when": [ ], "query_context": { "param_num":0, "fetch_cur_time":true, "calculable_items": [ ] } } } *************** Case 18 *************** explain update t2 set c3 = 'B' where c1 =1; { "explain_stmt": { "stmt_type":5, "table": [ { "table_id":1099511630878, "table_name":"t2", "alias_name":"", "table_type":0, "ref_id":1099511630878, "database_name":"explain_db" } ], "partition_express": [ ], "column": [ { "column_id":18, "column_name":"c3", "table_id":1099511630878, "obj_type":"VARCHAR", "length":32, "precision":32, "scale":0, "is_autoincrement":false, "cs_type":"utf8mb4_general_ci", "cs_level":2, "is_nullable":true, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"VARCHAR", "collation":"utf8mb4_general_ci", "coercibility":"IMPLICIT" }, "accuracy": { "length":32, "precision":32, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630878, "column_id":18, "expr_level":0 } }, { "column_id":16, "column_name":"c1", "table_id":1099511630878, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":false, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630878, "column_id":16, "expr_level":0 } } ], "input_columns": [ { "table_id":1099511630878, "table_name":"t2", "column": [ { "column_id":16, "column_name":"c1", "table_id":1099511630878, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":false, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630878, "column_id":16, "expr_level":0 } }, { "column_id":18, "column_name":"c3", "table_id":1099511630878, "obj_type":"VARCHAR", "length":32, "precision":32, "scale":0, "is_autoincrement":false, "cs_type":"utf8mb4_general_ci", "cs_level":2, "is_nullable":true, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"VARCHAR", "collation":"utf8mb4_general_ci", "coercibility":"IMPLICIT" }, "accuracy": { "length":32, "precision":32, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630878, "column_id":18, "expr_level":0 } } ] } ], "assign": [ { "table": { "table_id":1099511630878, "table_name":"t2", "alias_name":"", "table_type":0, "ref_id":1099511630878, "database_name":"explain_db" }, "assign": [ { "column": { "column_id":18, "column_name":"c3", "table_id":1099511630878, "obj_type":"VARCHAR", "length":32, "precision":32, "scale":0, "is_autoincrement":false, "cs_type":"utf8mb4_general_ci", "cs_level":2, "is_nullable":true, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"VARCHAR", "collation":"utf8mb4_general_ci", "coercibility":"IMPLICIT" }, "accuracy": { "length":32, "precision":32, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630878, "column_id":18, "expr_level":0 } }, "expression": { "item_type":"T_FUN_COLUMN_CONV", "result_type": { "meta": { "type":"BIGINT", "collation":"utf8mb4_general_ci", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "IS_FUNC", "IS_CALCULABLE_EXPR", "IS_CONST_EXPR", "CNT_CONST", "CNT_FUNC", "CNT_CALCULABLE_EXPR" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "func":"column_conv", "children": [ { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"utf8mb4_general_ci", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":22 } }, { "item_type":"T_INT", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "INT":32 } }, { "item_type":"T_BOOL", "result_type": { "meta": { "type":"TINYINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":0 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "TINYINT":1 } }, { "item_type":"T_VARCHAR", "result_type": { "meta": { "type":"VARCHAR", "collation":"utf8mb4_general_ci", "coercibility":"COERCIBLE" }, "accuracy": { "length":1, "precision":1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "VARCHAR":"B", "collation":"utf8mb4_general_ci" } } ] } } ] } ], "where": [ { "item_type":"T_OP_EQ", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":-1, "precision":-1, "scale":-1 }, "flag":1 }, "expr_info": [ "CNT_CONST", "CNT_COLUMN", "IS_SIMPLE_COND" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "children": [ { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630878, "column_id":16, "expr_level":0 }, { "item_type":"T_INT", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":1 }, "expr_info": [ "IS_CONST", "CNT_CONST" ], "rel_id": [ ], "base_column_id": [ ], "alias_column_id": [ ], "value": { "BIGINT":1 } } ] } ], "order_by": [ ], "limit":null, "offset":null, "hint": { "read_static":false, "frozen_version":-1, "topk_precision":-1, "sharding_minimum_row_count":0, "query_timeout":-1, "hotspot":false, "index": [ ], "read_consistency":0, "join_ordered":false, "join_order": [ ], "merge_hint_ids": [ ], "hash_hint_ids": [ ], "nl_hint_ids": [ ], "part_hints": [ ] }, "when": [ ], "query_context": { "param_num":0, "fetch_cur_time":true, "calculable_items": [ ] } } } *************** Case 19 *************** explain extended select c1 + c2 from t1; { "explain_stmt": { "stmt_type":1, "table": [ { "table_id":1099511630877, "table_name":"t1", "alias_name":"", "table_type":0, "ref_id":1099511630877, "database_name":"explain_db" } ], "joined_table": [ ], "partition_express": [ ], "column": [ { "column_id":16, "column_name":"c1", "table_id":1099511630877, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":false, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":16, "expr_level":0 } }, { "column_id":17, "column_name":"c2", "table_id":1099511630877, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":true, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":17, "expr_level":0 } } ], "select": [ { "expression": { "item_type":"T_OP_ADD", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":0 }, "expr_info": [ "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0, 1 ], "alias_column_id": [ ], "children": [ { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":16, "expr_level":0 }, { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":17, "expr_level":0 } ] }, "table_id":-1, "column_id":65519, "is_alias":false, "alias_name":"c1 + c2", "expr_name":"c1 + c2", "obj_type":"BIGINT", "length":65535, "precision":-1, "scale":0, "default": { "NULL":"NULL" }, "nullable":true } ], "distinct":false, "from": [ { "table_id":1099511630877, "is_join":false } ], "where": [ ], "group_by": [ ], "having": [ ], "aggr_func": [ ], "order_by": [ ], "limit":null, "offset":null, "for_update":false, "wait":-1, "show_stmt_ctx": { "is_from_show_stmt":false, "global_scope":false, "tenant_id":-1, "show_database_id":-1, "show_table_id":-1, "grants_user_id":-1 }, "when": [ ], "hint": { "read_static":false, "frozen_version":-1, "topk_precision":-1, "sharding_minimum_row_count":0, "query_timeout":-1, "hotspot":false, "index": [ ], "read_consistency":0, "join_ordered":false, "join_order": [ ], "merge_hint_ids": [ ], "hash_hint_ids": [ ], "nl_hint_ids": [ ], "part_hints": [ ] }, "query_context": { "param_num":0, "fetch_cur_time":true, "calculable_items": [ ] }, "current_level":0, "equal_sets": [ ], "child_stmts": [ ] } } *************** Case 20 *************** explain partitions select c1 + c2 from t1; { "explain_stmt": { "stmt_type":1, "table": [ { "table_id":1099511630877, "table_name":"t1", "alias_name":"", "table_type":0, "ref_id":1099511630877, "database_name":"explain_db" } ], "joined_table": [ ], "partition_express": [ ], "column": [ { "column_id":16, "column_name":"c1", "table_id":1099511630877, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":false, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":16, "expr_level":0 } }, { "column_id":17, "column_name":"c2", "table_id":1099511630877, "obj_type":"INT", "length":11, "precision":11, "scale":0, "is_autoincrement":false, "cs_type":"binary", "cs_level":5, "is_nullable":true, "auto_filled_timestamp":false, "default_value": { "NULL":"NULL" }, "expression": { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":17, "expr_level":0 } } ], "select": [ { "expression": { "item_type":"T_OP_ADD", "result_type": { "meta": { "type":"BIGINT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":65535, "precision":-1, "scale":0 }, "flag":0 }, "expr_info": [ "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0, 1 ], "alias_column_id": [ ], "children": [ { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":1 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 0 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":16, "expr_level":0 }, { "item_type":"T_REF_COLUMN", "result_type": { "meta": { "type":"INT", "collation":"binary", "coercibility":"NUMERIC" }, "accuracy": { "length":11, "precision":11, "scale":0 }, "flag":0 }, "expr_info": [ "IS_COLUMN", "CNT_COLUMN" ], "rel_id": [ 1 ], "base_column_id": [ 1 ], "alias_column_id": [ ], "table_id":1099511630877, "column_id":17, "expr_level":0 } ] }, "table_id":-1, "column_id":65519, "is_alias":false, "alias_name":"c1 + c2", "expr_name":"c1 + c2", "obj_type":"BIGINT", "length":65535, "precision":-1, "scale":0, "default": { "NULL":"NULL" }, "nullable":true } ], "distinct":false, "from": [ { "table_id":1099511630877, "is_join":false } ], "where": [ ], "group_by": [ ], "having": [ ], "aggr_func": [ ], "order_by": [ ], "limit":null, "offset":null, "for_update":false, "wait":-1, "show_stmt_ctx": { "is_from_show_stmt":false, "global_scope":false, "tenant_id":-1, "show_database_id":-1, "show_table_id":-1, "grants_user_id":-1 }, "when": [ ], "hint": { "read_static":false, "frozen_version":-1, "topk_precision":-1, "sharding_minimum_row_count":0, "query_timeout":-1, "hotspot":false, "index": [ ], "read_consistency":0, "join_ordered":false, "join_order": [ ], "merge_hint_ids": [ ], "hash_hint_ids": [ ], "nl_hint_ids": [ ], "part_hints": [ ] }, "query_context": { "param_num":0, "fetch_cur_time":true, "calculable_items": [ ] }, "current_level":0, "equal_sets": [ ], "child_stmts": [ ] } }