cherry pick pingcap#23687 to release-4.0

Signed-off-by: ti-srebot <ti-srebot@pingcap.com>
ti-srebot · Mar 30, 2021 · e720516 · e720516
1 parent 11a9254
commit e720516
Show file tree

Hide file tree

Showing 2 changed files with 14 additions and 1 deletion.
diff --git a/executor/aggfuncs/builder.go b/executor/aggfuncs/builder.go
@@ -150,9 +150,13 @@ func buildApproxPercentile(sctx sessionctx.Context, aggFuncDesc *aggregation.Agg
 
 	base := basePercentile{percent: int(percent), baseAggFunc: baseAggFunc{args: aggFuncDesc.Args, ordinal: ordinal}}
 
+	evalType := aggFuncDesc.Args[0].GetType().EvalType()
+	if aggFuncDesc.Args[0].GetType().Tp == mysql.TypeBit {
+		evalType = types.ETString // same as other aggregate function
+	}
 	switch aggFuncDesc.Mode {
 	case aggregation.CompleteMode, aggregation.Partial1Mode, aggregation.FinalMode:
-		switch aggFuncDesc.Args[0].GetType().EvalType() {
+		switch evalType {
 		case types.ETInt:
 			return &percentileOriginal4Int{base}
 		case types.ETReal:

diff --git a/expression/integration_test.go b/expression/integration_test.go
@@ -8080,3 +8080,12 @@ func (s *testIntegrationSerialSuite) TestIssue19116(c *C) {
 	tk.MustQuery("select coercibility(1);").Check(testkit.Rows("5"))
 	tk.MustQuery("select coercibility(1=1);").Check(testkit.Rows("5"))
 }
+
+func (s *testIntegrationSuite) TestApproximatePercentile(c *C) {
+	tk := testkit.NewTestKit(c, s.store)
+	tk.MustExec("use test")
+	tk.MustExec("drop table if exists t")
+	tk.MustExec("create table t (a bit(10))")
+	tk.MustExec("insert into t values(b'1111')")
+	tk.MustQuery("select approx_percentile(a, 10) from t").Check(testkit.Rows("<nil>"))
+}