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planner: support a hint to read from tiflash in planner #12479

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merged 14 commits into from
Oct 11, 2019
Merged

planner: support a hint to read from tiflash in planner #12479

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46baaae
support a hint to read from tiflash in planner
lzmhhh123 Sep 29, 2019
820b69b
add explain test for tiflash
lzmhhh123 Sep 29, 2019
5099bbb
fix ci
lzmhhh123 Sep 29, 2019
43c9668
address comments
lzmhhh123 Sep 30, 2019
6c86dce
address comments
lzmhhh123 Oct 8, 2019
50520cc
Merge branch 'master' into dev/support_access_from_flash_planner
lzmhhh123 Oct 8, 2019
264cccb
fix ci
lzmhhh123 Oct 8, 2019
f9f8380
address comments
lzmhhh123 Oct 8, 2019
d580919
fix ci
lzmhhh123 Oct 8, 2019
e0f347b
address comment
lzmhhh123 Oct 11, 2019
a059319
Merge branch 'master' into dev/support_access_from_flash_planner
lzmhhh123 Oct 11, 2019
ce38d93
Merge remote-tracking branch 'origin/master' into dev/support_access_…
lzmhhh123 Oct 11, 2019
515dcdb
Merge branch 'dev/support_access_from_flash_planner' of https://githu…
lzmhhh123 Oct 11, 2019
1755d8a
Merge branch 'master' into dev/support_access_from_flash_planner
sre-bot Oct 11, 2019
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56 changes: 28 additions & 28 deletions bindinfo/bind_test.go
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Original file line number Diff line number Diff line change
Expand Up @@ -330,23 +330,23 @@ func (s *testSuite) TestGlobalAndSessionBindingBothExist(c *C) {
tk.MustQuery("explain SELECT * from t1,t2 where t1.id = t2.id").Check(testkit.Rows(
"HashLeftJoin_8 12487.50 root inner join, inner:TableReader_15, equal:[eq(Column#1, Column#3)]",
"├─TableReader_12 9990.00 root data:Selection_11",
"│ └─Selection_11 9990.00 cop not(isnull(Column#1))",
"│ └─TableScan_10 10000.00 cop table:t1, range:[-inf,+inf], keep order:false, stats:pseudo",
"│ └─Selection_11 9990.00 cop[tikv] not(isnull(Column#1))",
"│ └─TableScan_10 10000.00 cop[tikv] table:t1, range:[-inf,+inf], keep order:false, stats:pseudo",
"└─TableReader_15 9990.00 root data:Selection_14",
" └─Selection_14 9990.00 cop not(isnull(Column#3))",
" └─TableScan_13 10000.00 cop table:t2, range:[-inf,+inf], keep order:false, stats:pseudo",
" └─Selection_14 9990.00 cop[tikv] not(isnull(Column#3))",
" └─TableScan_13 10000.00 cop[tikv] table:t2, range:[-inf,+inf], keep order:false, stats:pseudo",
))

tk.MustQuery("explain SELECT /*+ TIDB_SMJ(t1, t2) */ * from t1,t2 where t1.id = t2.id").Check(testkit.Rows(
"MergeJoin_7 12487.50 root inner join, left key:Column#1, right key:Column#3",
"├─Sort_11 9990.00 root Column#1:asc",
"│ └─TableReader_10 9990.00 root data:Selection_9",
"│ └─Selection_9 9990.00 cop not(isnull(Column#1))",
"│ └─TableScan_8 10000.00 cop table:t1, range:[-inf,+inf], keep order:false, stats:pseudo",
"│ └─Selection_9 9990.00 cop[tikv] not(isnull(Column#1))",
"│ └─TableScan_8 10000.00 cop[tikv] table:t1, range:[-inf,+inf], keep order:false, stats:pseudo",
"└─Sort_15 9990.00 root Column#3:asc",
" └─TableReader_14 9990.00 root data:Selection_13",
" └─Selection_13 9990.00 cop not(isnull(Column#3))",
" └─TableScan_12 10000.00 cop table:t2, range:[-inf,+inf], keep order:false, stats:pseudo",
" └─Selection_13 9990.00 cop[tikv] not(isnull(Column#3))",
" └─TableScan_12 10000.00 cop[tikv] table:t2, range:[-inf,+inf], keep order:false, stats:pseudo",
))

tk.MustExec("create global binding for SELECT * from t1,t2 where t1.id = t2.id using SELECT /*+ TIDB_SMJ(t1, t2) */ * from t1,t2 where t1.id = t2.id")
Expand All @@ -356,12 +356,12 @@ func (s *testSuite) TestGlobalAndSessionBindingBothExist(c *C) {
"MergeJoin_7 12487.50 root inner join, left key:Column#1, right key:Column#3",
"├─Sort_11 9990.00 root Column#1:asc",
"│ └─TableReader_10 9990.00 root data:Selection_9",
"│ └─Selection_9 9990.00 cop not(isnull(Column#1))",
"│ └─TableScan_8 10000.00 cop table:t1, range:[-inf,+inf], keep order:false, stats:pseudo",
"│ └─Selection_9 9990.00 cop[tikv] not(isnull(Column#1))",
"│ └─TableScan_8 10000.00 cop[tikv] table:t1, range:[-inf,+inf], keep order:false, stats:pseudo",
"└─Sort_15 9990.00 root Column#3:asc",
" └─TableReader_14 9990.00 root data:Selection_13",
" └─Selection_13 9990.00 cop not(isnull(Column#3))",
" └─TableScan_12 10000.00 cop table:t2, range:[-inf,+inf], keep order:false, stats:pseudo",
" └─Selection_13 9990.00 cop[tikv] not(isnull(Column#3))",
" └─TableScan_12 10000.00 cop[tikv] table:t2, range:[-inf,+inf], keep order:false, stats:pseudo",
))
pb := &dto.Metric{}
metrics.BindUsageCounter.WithLabelValues(metrics.ScopeGlobal).Write(pb)
Expand All @@ -372,11 +372,11 @@ func (s *testSuite) TestGlobalAndSessionBindingBothExist(c *C) {
tk.MustQuery("explain SELECT * from t1,t2 where t1.id = t2.id").Check(testkit.Rows(
"HashLeftJoin_8 12487.50 root inner join, inner:TableReader_15, equal:[eq(Column#1, Column#3)]",
"├─TableReader_12 9990.00 root data:Selection_11",
"│ └─Selection_11 9990.00 cop not(isnull(Column#1))",
"│ └─TableScan_10 10000.00 cop table:t1, range:[-inf,+inf], keep order:false, stats:pseudo",
"│ └─Selection_11 9990.00 cop[tikv] not(isnull(Column#1))",
"│ └─TableScan_10 10000.00 cop[tikv] table:t1, range:[-inf,+inf], keep order:false, stats:pseudo",
"└─TableReader_15 9990.00 root data:Selection_14",
" └─Selection_14 9990.00 cop not(isnull(Column#3))",
" └─TableScan_13 10000.00 cop table:t2, range:[-inf,+inf], keep order:false, stats:pseudo",
" └─Selection_14 9990.00 cop[tikv] not(isnull(Column#3))",
" └─TableScan_13 10000.00 cop[tikv] table:t2, range:[-inf,+inf], keep order:false, stats:pseudo",
))
}

Expand All @@ -392,23 +392,23 @@ func (s *testSuite) TestExplain(c *C) {
tk.MustQuery("explain SELECT * from t1,t2 where t1.id = t2.id").Check(testkit.Rows(
"HashLeftJoin_8 12487.50 root inner join, inner:TableReader_15, equal:[eq(Column#1, Column#3)]",
"├─TableReader_12 9990.00 root data:Selection_11",
"│ └─Selection_11 9990.00 cop not(isnull(Column#1))",
"│ └─TableScan_10 10000.00 cop table:t1, range:[-inf,+inf], keep order:false, stats:pseudo",
"│ └─Selection_11 9990.00 cop[tikv] not(isnull(Column#1))",
"│ └─TableScan_10 10000.00 cop[tikv] table:t1, range:[-inf,+inf], keep order:false, stats:pseudo",
"└─TableReader_15 9990.00 root data:Selection_14",
" └─Selection_14 9990.00 cop not(isnull(Column#3))",
" └─TableScan_13 10000.00 cop table:t2, range:[-inf,+inf], keep order:false, stats:pseudo",
" └─Selection_14 9990.00 cop[tikv] not(isnull(Column#3))",
" └─TableScan_13 10000.00 cop[tikv] table:t2, range:[-inf,+inf], keep order:false, stats:pseudo",
))

tk.MustQuery("explain SELECT /*+ TIDB_SMJ(t1, t2) */ * from t1,t2 where t1.id = t2.id").Check(testkit.Rows(
"MergeJoin_7 12487.50 root inner join, left key:Column#1, right key:Column#3",
"├─Sort_11 9990.00 root Column#1:asc",
"│ └─TableReader_10 9990.00 root data:Selection_9",
"│ └─Selection_9 9990.00 cop not(isnull(Column#1))",
"│ └─TableScan_8 10000.00 cop table:t1, range:[-inf,+inf], keep order:false, stats:pseudo",
"│ └─Selection_9 9990.00 cop[tikv] not(isnull(Column#1))",
"│ └─TableScan_8 10000.00 cop[tikv] table:t1, range:[-inf,+inf], keep order:false, stats:pseudo",
"└─Sort_15 9990.00 root Column#3:asc",
" └─TableReader_14 9990.00 root data:Selection_13",
" └─Selection_13 9990.00 cop not(isnull(Column#3))",
" └─TableScan_12 10000.00 cop table:t2, range:[-inf,+inf], keep order:false, stats:pseudo",
" └─Selection_13 9990.00 cop[tikv] not(isnull(Column#3))",
" └─TableScan_12 10000.00 cop[tikv] table:t2, range:[-inf,+inf], keep order:false, stats:pseudo",
))

tk.MustExec("create global binding for SELECT * from t1,t2 where t1.id = t2.id using SELECT /*+ TIDB_SMJ(t1, t2) */ * from t1,t2 where t1.id = t2.id")
Expand All @@ -417,12 +417,12 @@ func (s *testSuite) TestExplain(c *C) {
"MergeJoin_7 12487.50 root inner join, left key:Column#1, right key:Column#3",
"├─Sort_11 9990.00 root Column#1:asc",
"│ └─TableReader_10 9990.00 root data:Selection_9",
"│ └─Selection_9 9990.00 cop not(isnull(Column#1))",
"│ └─TableScan_8 10000.00 cop table:t1, range:[-inf,+inf], keep order:false, stats:pseudo",
"│ └─Selection_9 9990.00 cop[tikv] not(isnull(Column#1))",
"│ └─TableScan_8 10000.00 cop[tikv] table:t1, range:[-inf,+inf], keep order:false, stats:pseudo",
"└─Sort_15 9990.00 root Column#3:asc",
" └─TableReader_14 9990.00 root data:Selection_13",
" └─Selection_13 9990.00 cop not(isnull(Column#3))",
" └─TableScan_12 10000.00 cop table:t2, range:[-inf,+inf], keep order:false, stats:pseudo",
" └─Selection_13 9990.00 cop[tikv] not(isnull(Column#3))",
" └─TableScan_12 10000.00 cop[tikv] table:t2, range:[-inf,+inf], keep order:false, stats:pseudo",
))

tk.MustExec("drop global binding for SELECT * from t1,t2 where t1.id = t2.id")
Expand Down
24 changes: 12 additions & 12 deletions cmd/explaintest/r/access_path_selection.result
View file
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Original file line number Diff line number Diff line change
Expand Up @@ -8,37 +8,37 @@ KEY `IDX_ab` (`a`, `b`)
explain select a from access_path_selection where a < 3;
id count task operator info
IndexReader_6 3323.33 root index:IndexScan_5
└─IndexScan_5 3323.33 cop table:access_path_selection, index:a, range:[-inf,3), keep order:false, stats:pseudo
└─IndexScan_5 3323.33 cop[tikv] table:access_path_selection, index:a, range:[-inf,3), keep order:false, stats:pseudo
explain select a, b from access_path_selection where a < 3;
id count task operator info
IndexReader_6 3323.33 root index:IndexScan_5
└─IndexScan_5 3323.33 cop table:access_path_selection, index:a, b, range:[-inf,3), keep order:false, stats:pseudo
└─IndexScan_5 3323.33 cop[tikv] table:access_path_selection, index:a, b, range:[-inf,3), keep order:false, stats:pseudo
explain select a, b from access_path_selection where b < 3;
id count task operator info
IndexReader_13 3323.33 root index:Selection_12
└─Selection_12 3323.33 cop lt(Column#2, 3)
└─IndexScan_11 10000.00 cop table:access_path_selection, index:a, b, range:[NULL,+inf], keep order:false, stats:pseudo
└─Selection_12 3323.33 cop[tikv] lt(Column#2, 3)
└─IndexScan_11 10000.00 cop[tikv] table:access_path_selection, index:a, b, range:[NULL,+inf], keep order:false, stats:pseudo
explain select a, b from access_path_selection where a < 3 and b < 3;
id count task operator info
IndexReader_11 1104.45 root index:Selection_10
└─Selection_10 1104.45 cop lt(Column#2, 3)
└─IndexScan_9 3323.33 cop table:access_path_selection, index:a, b, range:[-inf,3), keep order:false, stats:pseudo
└─Selection_10 1104.45 cop[tikv] lt(Column#2, 3)
└─IndexScan_9 3323.33 cop[tikv] table:access_path_selection, index:a, b, range:[-inf,3), keep order:false, stats:pseudo
explain select a, b from access_path_selection where a > 10 order by _tidb_rowid;
id count task operator info
Projection_6 3333.33 root Column#1, Column#2
└─TableReader_13 3333.33 root data:Selection_12
└─Selection_12 3333.33 cop gt(Column#1, 10)
└─TableScan_11 10000.00 cop table:access_path_selection, range:[-inf,+inf], keep order:true, stats:pseudo
└─Selection_12 3333.33 cop[tikv] gt(Column#1, 10)
└─TableScan_11 10000.00 cop[tikv] table:access_path_selection, range:[-inf,+inf], keep order:true, stats:pseudo
explain select max(_tidb_rowid) from access_path_selection;
id count task operator info
StreamAgg_13 1.00 root funcs:max(Column#3)
└─Limit_17 1.00 root offset:0, count:1
└─TableReader_27 1.00 root data:Limit_26
└─Limit_26 1.00 cop offset:0, count:1
└─TableScan_25 1.25 cop table:access_path_selection, range:[-inf,+inf], keep order:true, desc, stats:pseudo
└─Limit_26 1.00 cop[tikv] offset:0, count:1
└─TableScan_25 1.25 cop[tikv] table:access_path_selection, range:[-inf,+inf], keep order:true, desc, stats:pseudo
explain select count(1) from access_path_selection;
id count task operator info
StreamAgg_28 1.00 root funcs:count(Column#7)
└─IndexReader_29 1.00 root index:StreamAgg_8
└─StreamAgg_8 1.00 cop funcs:count(1)
└─IndexScan_25 10000.00 cop table:access_path_selection, index:a, range:[NULL,+inf], keep order:false, stats:pseudo
└─StreamAgg_8 1.00 cop[tikv] funcs:count(1)
└─IndexScan_25 10000.00 cop[tikv] table:access_path_selection, index:a, range:[NULL,+inf], keep order:false, stats:pseudo
32 changes: 32 additions & 0 deletions cmd/explaintest/r/access_tiflash.result
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Original file line number Diff line number Diff line change
@@ -0,0 +1,32 @@
drop table if exists t, tt;
create table t(a int, b int, index ia(a));
desc select avg(a) from t;
id count task operator info
StreamAgg_20 1.00 root funcs:avg(Column#8, Column#9)
└─IndexReader_21 1.00 root index:StreamAgg_8
└─StreamAgg_8 1.00 cop[tikv] funcs:avg(Column#1)
└─IndexScan_19 10000.00 cop[tikv] table:t, index:a, range:[NULL,+inf], keep order:false, stats:pseudo
desc select /*+ read_from_storage(tiflash[t]) */ avg(a) from t;
id count task operator info
StreamAgg_16 1.00 root funcs:avg(Column#8, Column#9)
└─TableReader_17 1.00 root data:StreamAgg_8
└─StreamAgg_8 1.00 cop[tiflash] funcs:count(Column#1), sum(Column#1)
└─TableScan_15 10000.00 cop[tiflash] table:t, range:[-inf,+inf], keep order:false, stats:pseudo
desc select /*+ read_from_storage(tiflash[t]) */ sum(a) from t;
id count task operator info
StreamAgg_16 1.00 root funcs:sum(Column#7)
└─TableReader_17 1.00 root data:StreamAgg_8
└─StreamAgg_8 1.00 cop[tiflash] funcs:sum(Column#1)
└─TableScan_15 10000.00 cop[tiflash] table:t, range:[-inf,+inf], keep order:false, stats:pseudo
desc select /*+ read_from_storage(tiflash[t]) */ sum(a+1) from t;
id count task operator info
StreamAgg_16 1.00 root funcs:sum(Column#7)
└─TableReader_17 1.00 root data:StreamAgg_8
└─StreamAgg_8 1.00 cop[tiflash] funcs:sum(plus(Column#1, 1))
└─TableScan_15 10000.00 cop[tiflash] table:t, range:[-inf,+inf], keep order:false, stats:pseudo
desc select /*+ read_from_storage(tiflash[t]) */ sum(isnull(a)) from t;
id count task operator info
StreamAgg_16 1.00 root funcs:sum(Column#7)
└─TableReader_17 1.00 root data:StreamAgg_8
└─StreamAgg_8 1.00 cop[tiflash] funcs:sum(isnull(Column#1))
└─TableScan_15 10000.00 cop[tiflash] table:t, range:[-inf,+inf], keep order:false, stats:pseudo
22 changes: 11 additions & 11 deletions cmd/explaintest/r/black_list.result
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Original file line number Diff line number Diff line change
Expand Up @@ -4,53 +4,53 @@ create table t (a int);
explain select * from t where a < 1;
id count task operator info
TableReader_7 3323.33 root data:Selection_6
└─Selection_6 3323.33 cop lt(Column#1, 1)
└─TableScan_5 10000.00 cop table:t, range:[-inf,+inf], keep order:false, stats:pseudo
└─Selection_6 3323.33 cop[tikv] lt(Column#1, 1)
└─TableScan_5 10000.00 cop[tikv] table:t, range:[-inf,+inf], keep order:false, stats:pseudo
insert into mysql.opt_rule_blacklist values('predicate_push_down');
admin reload opt_rule_blacklist;

explain select * from t where a < 1;
id count task operator info
Selection_5 8000.00 root lt(Column#1, 1)
└─TableReader_7 10000.00 root data:TableScan_6
└─TableScan_6 10000.00 cop table:t, range:[-inf,+inf], keep order:false, stats:pseudo
└─TableScan_6 10000.00 cop[tikv] table:t, range:[-inf,+inf], keep order:false, stats:pseudo
delete from mysql.opt_rule_blacklist where name='predicate_push_down';
admin reload opt_rule_blacklist;

explain select * from t where a < 1;
id count task operator info
TableReader_7 3323.33 root data:Selection_6
└─Selection_6 3323.33 cop lt(Column#1, 1)
└─TableScan_5 10000.00 cop table:t, range:[-inf,+inf], keep order:false, stats:pseudo
└─Selection_6 3323.33 cop[tikv] lt(Column#1, 1)
└─TableScan_5 10000.00 cop[tikv] table:t, range:[-inf,+inf], keep order:false, stats:pseudo
insert into mysql.expr_pushdown_blacklist values('<');
admin reload expr_pushdown_blacklist;

explain select * from t where a < 1;
id count task operator info
Selection_5 8000.00 root lt(Column#1, 1)
└─TableReader_7 10000.00 root data:TableScan_6
└─TableScan_6 10000.00 cop table:t, range:[-inf,+inf], keep order:false, stats:pseudo
└─TableScan_6 10000.00 cop[tikv] table:t, range:[-inf,+inf], keep order:false, stats:pseudo
delete from mysql.expr_pushdown_blacklist where name='<';
admin reload expr_pushdown_blacklist;

explain select * from t where a < 1;
id count task operator info
TableReader_7 3323.33 root data:Selection_6
└─Selection_6 3323.33 cop lt(Column#1, 1)
└─TableScan_5 10000.00 cop table:t, range:[-inf,+inf], keep order:false, stats:pseudo
└─Selection_6 3323.33 cop[tikv] lt(Column#1, 1)
└─TableScan_5 10000.00 cop[tikv] table:t, range:[-inf,+inf], keep order:false, stats:pseudo
insert into mysql.expr_pushdown_blacklist values('lt');
admin reload expr_pushdown_blacklist;

explain select * from t where a < 1;
id count task operator info
Selection_5 8000.00 root lt(Column#1, 1)
└─TableReader_7 10000.00 root data:TableScan_6
└─TableScan_6 10000.00 cop table:t, range:[-inf,+inf], keep order:false, stats:pseudo
└─TableScan_6 10000.00 cop[tikv] table:t, range:[-inf,+inf], keep order:false, stats:pseudo
delete from mysql.expr_pushdown_blacklist where name='lt';
admin reload expr_pushdown_blacklist;

explain select * from t where a < 1;
id count task operator info
TableReader_7 3323.33 root data:Selection_6
└─Selection_6 3323.33 cop lt(Column#1, 1)
└─TableScan_5 10000.00 cop table:t, range:[-inf,+inf], keep order:false, stats:pseudo
└─Selection_6 3323.33 cop[tikv] lt(Column#1, 1)
└─TableScan_5 10000.00 cop[tikv] table:t, range:[-inf,+inf], keep order:false, stats:pseudo
12 changes: 6 additions & 6 deletions cmd/explaintest/r/explain-non-select-stmt.result
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Original file line number Diff line number Diff line change
Expand Up @@ -8,22 +8,22 @@ explain insert into t select * from t;
id count task operator info
Insert_1 N/A root N/A
└─TableReader_7 10000.00 root data:TableScan_6
└─TableScan_6 10000.00 cop table:t, range:[-inf,+inf], keep order:false, stats:pseudo
└─TableScan_6 10000.00 cop[tikv] table:t, range:[-inf,+inf], keep order:false, stats:pseudo
explain delete from t where a > 100;
id count task operator info
Delete_3 N/A root N/A
└─TableReader_6 3333.33 root data:Selection_5
└─Selection_5 3333.33 cop gt(Column#1, 100)
└─TableScan_4 10000.00 cop table:t, range:[-inf,+inf], keep order:false, stats:pseudo
└─Selection_5 3333.33 cop[tikv] gt(Column#1, 100)
└─TableScan_4 10000.00 cop[tikv] table:t, range:[-inf,+inf], keep order:false, stats:pseudo
explain update t set b = 100 where a = 200;
id count task operator info
Update_3 N/A root N/A
└─TableReader_6 10.00 root data:Selection_5
└─Selection_5 10.00 cop eq(Column#1, 200)
└─TableScan_4 10000.00 cop table:t, range:[-inf,+inf], keep order:false, stats:pseudo
└─Selection_5 10.00 cop[tikv] eq(Column#1, 200)
└─TableScan_4 10000.00 cop[tikv] table:t, range:[-inf,+inf], keep order:false, stats:pseudo
explain replace into t select a, 100 from t;
id count task operator info
Insert_1 N/A root N/A
└─Projection_5 10000.00 root Column#3, 100
└─TableReader_7 10000.00 root data:TableScan_6
└─TableScan_6 10000.00 cop table:t, range:[-inf,+inf], keep order:false, stats:pseudo
└─TableScan_6 10000.00 cop[tikv] table:t, range:[-inf,+inf], keep order:false, stats:pseudo
4 changes: 2 additions & 2 deletions cmd/explaintest/r/explain.result
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Original file line number Diff line number Diff line change
Expand Up @@ -31,11 +31,11 @@ id count task operator info
StreamAgg_8 8000.00 root group by:Column#6, funcs:group_concat(Column#0, ",")
└─Projection_18 10000.00 root cast(Column#2), Column#1
└─TableReader_15 10000.00 root data:TableScan_14
└─TableScan_14 10000.00 cop table:t, range:[-inf,+inf], keep order:true, stats:pseudo
└─TableScan_14 10000.00 cop[tikv] table:t, range:[-inf,+inf], keep order:true, stats:pseudo
explain select group_concat(a, b) from t group by id;
id count task operator info
StreamAgg_8 8000.00 root group by:Column#6, funcs:group_concat(Column#0, Column#0, ",")
└─Projection_18 10000.00 root cast(Column#2), cast(Column#3), Column#1
└─TableReader_15 10000.00 root data:TableScan_14
└─TableScan_14 10000.00 cop table:t, range:[-inf,+inf], keep order:true, stats:pseudo
└─TableScan_14 10000.00 cop[tikv] table:t, range:[-inf,+inf], keep order:true, stats:pseudo
drop table t;
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