ef1bb9819a
When we create a materialized view for multiple tables, users may not figure out the partition rule for the materialized view, because the query result can be too complex. If the query result doesn't match one of the partition rules, the insertion will fail.
We can resolve this issue by mapping the partition rule of base table to the materialized view. As a result, users don't need specify the partition rules and query results are all valid because they are retrieved from the partitions of the base table.
## Use case
mysql> CREATE TABLE t1 (pk INT NOT NULL, v1 INT SUM) PARTITION BY RANGE(pk) (
-> PARTITION p1 VALUES LESS THAN ('10'),
-> PARTITION p2 VALUES LESS THAN ('90')
-> )
-> DISTRIBUTED BY HASH(pk)
-> PROPERTIES ('replication_num' = '1');
Query OK, 0 rows affected (0.04 sec)
mysql> CREATE TABLE t2 (pk INT NOT NULL, v2 INT SUM) PARTITION BY LIST(pk) (
-> PARTITION odd VALUES IN ('10', '30', '50', '70', '90'),
-> PARTITION even VALUES IN ('20', '40', '60', '80')
-> )
-> DISTRIBUTED BY HASH(pk)
-> PROPERTIES ('replication_num' = '1');
Query OK, 0 rows affected (0.02 sec)
mysql> CREATE MATERIALIZED VIEW mv BUILD IMMEDIATE REFRESH COMPLETE
-> KEY (mpk) PARTITION BY (t1.pk) DISTRIBUTED BY HASH(mpk) PROPERTIES ('replication_num' = '1')
-> AS SELECT t1.pk AS mpk, v1, v2 FROM t1, t2 WHERE t1.pk = t2.pk;
Query OK, 0 rows affected (0.10 sec)
mysql> SHOW CREATE TABLE mv;
+-------------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Materialized View | Create Materialized View |
+-------------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| mv | CREATE MATERIALIZED VIEW `mv`
BUILD IMMEDIATE REFRESH COMPLETE ON DEMAND
KEY(`mpk`)
PARTITION BY RANGE(`mpk`)
(PARTITION p1 VALUES [("-2147483648"), ("10")),
PARTITION p2 VALUES [("10"), ("90")))
DISTRIBUTED BY HASH(`mpk`) BUCKETS 10
PROPERTIES (
"replication_allocation" = "tag.location.default: 1",
"in_memory" = "false",
"storage_format" = "V2",
"disable_auto_compaction" = "false"
)
AS SELECT `t1`.`pk` AS `mpk`, `v1` AS `v1`, `v2` AS `v2` FROM `default_cluster:dev`.`t1` , `default_cluster:dev`.`t2` WHERE `t1`.`pk` = `t2`.`pk`; |
+-------------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)
# Licensed to the Apache Software Foundation (ASF) under one # or more contributor license agreements. See the NOTICE file # distributed with this work for additional information # regarding copyright ownership. The ASF licenses this file # to you under the Apache License, Version 2.0 (the # "License"); you may not use this file except in compliance # with the License. You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, # software distributed under the License is distributed on an # "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY # KIND, either express or implied. See the License for the # specific language governing permissions and limitations # under the License. # fe-common This module is used to store some common classes of other modules. # spark-dpp This module is Spark DPP program, used for Spark Load function. Depends: fe-common # fe-core This module is the main process module of FE. Depends: fe-common, spark-dpp