45 lines
2.3 KiB
Plaintext
45 lines
2.3 KiB
Plaintext
CREATE TABLE `access_path_selection` (
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`a` int,
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`b` int,
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KEY `IDX_a` (`a`),
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KEY `IDX_b` (`b`),
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KEY `IDX_ab` (`a`, `b`)
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);
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explain select a from access_path_selection where a < 3;
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id count task operator info
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IndexReader_6 3323.33 root index:IndexScan_5
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└─IndexScan_5 3323.33 cop[tikv] table:access_path_selection, index:a, range:[-inf,3), keep order:false, stats:pseudo
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explain select a, b from access_path_selection where a < 3;
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id count task operator info
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IndexReader_6 3323.33 root index:IndexScan_5
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└─IndexScan_5 3323.33 cop[tikv] table:access_path_selection, index:a, b, range:[-inf,3), keep order:false, stats:pseudo
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explain select a, b from access_path_selection where b < 3;
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id count task operator info
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TableReader_7 3323.33 root data:Selection_6
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└─Selection_6 3323.33 cop[tikv] lt(Column#2, 3)
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└─TableScan_5 10000.00 cop[tikv] table:access_path_selection, range:[-inf,+inf], keep order:false, stats:pseudo
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explain select a, b from access_path_selection where a < 3 and b < 3;
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id count task operator info
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IndexReader_11 1104.45 root index:Selection_10
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└─Selection_10 1104.45 cop[tikv] lt(Column#2, 3)
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└─IndexScan_9 3323.33 cop[tikv] table:access_path_selection, index:a, b, range:[-inf,3), keep order:false, stats:pseudo
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explain select a, b from access_path_selection where a > 10 order by _tidb_rowid;
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id count task operator info
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Projection_6 3333.33 root Column#1, Column#2
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└─TableReader_13 3333.33 root data:Selection_12
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└─Selection_12 3333.33 cop[tikv] gt(Column#1, 10)
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└─TableScan_11 10000.00 cop[tikv] table:access_path_selection, range:[-inf,+inf], keep order:true, stats:pseudo
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explain select max(_tidb_rowid) from access_path_selection;
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id count task operator info
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StreamAgg_13 1.00 root funcs:max(Column#3)
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└─Limit_17 1.00 root offset:0, count:1
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└─TableReader_27 1.00 root data:Limit_26
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└─Limit_26 1.00 cop[tikv] offset:0, count:1
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└─TableScan_25 1.25 cop[tikv] table:access_path_selection, range:[-inf,+inf], keep order:true, desc, stats:pseudo
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explain select count(1) from access_path_selection;
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id count task operator info
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StreamAgg_28 1.00 root funcs:count(Column#19)
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└─TableReader_29 1.00 root data:StreamAgg_8
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└─StreamAgg_8 1.00 cop[tikv] funcs:count(1)
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└─TableScan_24 10000.00 cop[tikv] table:access_path_selection, range:[-inf,+inf], keep order:false, stats:pseudo
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