planner/core: keep sort operator when ordered by tablesample (#48315)

close #48253
pingcap · Nov 8, 2023 · 83e39bc · 83e39bc
1 parent 184aa7e
commit 83e39bc
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Showing 3 changed files with 34 additions and 19 deletions.
diff --git a/pkg/planner/core/find_best_task.go b/pkg/planner/core/find_best_task.go
@@ -1084,12 +1084,7 @@ func (ds *DataSource) findBestTask(prop *property.PhysicalProperty, planCounter
 		}
 
 		ds.storeTask(prop, t)
-		if ds.SampleInfo != nil && !t.invalid() {
-			if _, ok := t.plan().(*PhysicalTableSample); !ok {
-				warning := expression.ErrInvalidTableSample.GenWithStackByArgs("plan not supported")
-				ds.SCtx().GetSessionVars().StmtCtx.AppendWarning(warning)
-			}
-		}
+		err = validateTableSamplePlan(ds, t, err)
 	}()
 
 	t, err = ds.tryToGetDualTask()
@@ -2243,10 +2238,8 @@ func (ds *DataSource) convertToSampleTable(prop *property.PhysicalProperty,
 		return invalidTask, nil
 	}
 	if candidate.isMatchProp {
-		// TableSample on partition table can't keep order.
-		if ds.tableInfo.GetPartitionInfo() != nil {
-			return invalidTask, nil
-		}
+		// Disable keep order property for sample table path.
+		return invalidTask, nil
 	}
 	p := PhysicalTableSample{
 		TableSampleInfo: ds.SampleInfo,
@@ -2618,3 +2611,15 @@ func pushDownNot(ctx sessionctx.Context, conds []expression.Expression) []expres
 	}
 	return conds
 }
+
+func validateTableSamplePlan(ds *DataSource, t task, err error) error {
+	if err != nil {
+		return err
+	}
+	if ds.SampleInfo != nil && !t.invalid() {
+		if _, ok := t.plan().(*PhysicalTableSample); !ok {
+			return expression.ErrInvalidTableSample.GenWithStackByArgs("plan not supported")
+		}
+	}
+	return nil
+}
diff --git a/tests/integrationtest/r/executor/sample.result b/tests/integrationtest/r/executor/sample.result
@@ -178,12 +178,14 @@ a
 2100
 4500
 select a from t use index (idx_0) tablesample regions() order by a;
-a
-1000
-1001
-2100
-4500
-show warnings;
-Level	Code	Message
-Warning	8128	Invalid TABLESAMPLE: plan not supported
+Error 8128 (HY000): Invalid TABLESAMPLE: plan not supported
+DROP TABLE IF EXISTS a;
+CREATE TABLE a (pk bigint unsigned primary key clustered, v text);
+INSERT INTO a WITH RECURSIVE b(pk) AS (SELECT 1 UNION ALL SELECT pk+1 FROM b WHERE pk < 1000) SELECT pk, 'a' FROM b;
+INSERT INTO a WITH RECURSIVE b(pk) AS (SELECT 1 UNION ALL SELECT pk+1 FROM b WHERE pk < 1000) SELECT pk + (1<<63), 'b' FROM b;
+SPLIT TABLE a BY (500);
+SELECT * FROM a TABLESAMPLE REGIONS() ORDER BY pk;
+pk	v
+500	a
+9223372036854775809	b
 set @@global.tidb_scatter_region=default;
diff --git a/tests/integrationtest/t/executor/sample.test b/tests/integrationtest/t/executor/sample.test
@@ -119,7 +119,15 @@ split table t between (0) and (10000) regions 5;
 insert into t values (1000, 1, '1'), (1001, 1, '1'), (2100, 2, '2'), (4500, 3, '3');
 create index idx_0 on t (b);
 select a from t tablesample regions() order by a;
+-- error 8128
 select a from t use index (idx_0) tablesample regions() order by a;
-show warnings;
+
+# TestTableSampleUnsignedIntHandle
+DROP TABLE IF EXISTS a;
+CREATE TABLE a (pk bigint unsigned primary key clustered, v text);
+INSERT INTO a WITH RECURSIVE b(pk) AS (SELECT 1 UNION ALL SELECT pk+1 FROM b WHERE pk < 1000) SELECT pk, 'a' FROM b;
+INSERT INTO a WITH RECURSIVE b(pk) AS (SELECT 1 UNION ALL SELECT pk+1 FROM b WHERE pk < 1000) SELECT pk + (1<<63), 'b' FROM b;
+SPLIT TABLE a BY (500);
+SELECT * FROM a TABLESAMPLE REGIONS() ORDER BY pk;
 
 set @@global.tidb_scatter_region=default;