ddl: Only warn of subpartitions, still allow first level partitioning

ddl/db_partition_test.go

@@ -399,14 +399,56 @@ func TestCreateTableWithHashPartition(t *testing.T) {
                                        PARTITION p0 VALUES LESS THAN (100),
                                        PARTITION p1 VALUES LESS THAN (200),
                                        PARTITION p2 VALUES LESS THAN MAXVALUE)`)
-	tk.MustGetErrCode("select * from t_sub partition (p0)", errno.ErrPartitionClauseOnNonpartitioned)
+	tk.MustQuery(`show warnings`).Check(testkit.Rows("Warning 8200 Unsupported subpartitioning, only using RANGE partitioning"))
+	tk.MustQuery("select * from t_sub partition (p0)").Check(testkit.Rows())
+	tk.MustQuery("show create table t_sub").Check(testkit.Rows("" +
+		"t_sub CREATE TABLE `t_sub` (\n" +
+		"  `a` int(11) DEFAULT NULL,\n" +
+		"  `b` varchar(128) DEFAULT NULL\n" +
+		") ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin\n" +
+		"PARTITION BY RANGE (`a`)\n" +
+		"(PARTITION `p0` VALUES LESS THAN (100),\n" +
+		" PARTITION `p1` VALUES LESS THAN (200),\n" +
+		" PARTITION `p2` VALUES LESS THAN (MAXVALUE))"))
 
 	// Fix create partition table using extract() function as partition key.
 	tk.MustExec("create table t2 (a date, b datetime) partition by hash (EXTRACT(YEAR_MONTH FROM a)) partitions 7")
 	tk.MustExec("create table t3 (a int, b int) partition by hash(ceiling(a-b)) partitions 10")
 	tk.MustExec("create table t4 (a int, b int) partition by hash(floor(a-b)) partitions 10")
 }
 
+func TestSubPartitioning(t *testing.T) {
+	store := testkit.CreateMockStore(t, mockstore.WithDDLChecker())
+
+	tk := testkit.NewTestKit(t, store)
+	tk.MustExec("use test")
+	tk.MustExec(`create table t (a int) partition by range (a) subpartition by hash (a) subpartitions 2 (partition pMax values less than (maxvalue))`)
+	tk.MustQuery(`show warnings`).Check(testkit.Rows("Warning 8200 Unsupported subpartitioning, only using RANGE partitioning"))
+	tk.MustQuery(`show create table t`).Check(testkit.Rows("" +
+		"t CREATE TABLE `t` (\n" +
+		"  `a` int(11) DEFAULT NULL\n" +
+		") ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin\n" +
+		"PARTITION BY RANGE (`a`)\n" +
+		"(PARTITION `pMax` VALUES LESS THAN (MAXVALUE))"))
+	tk.MustExec(`drop table t`)
+
+	tk.MustExec(`create table t (a int) partition by list (a) subpartition by key (a) subpartitions 2 (partition pMax values in (1,3,4))`)
+	tk.MustQuery(`show warnings`).Check(testkit.Rows("Warning 8200 Unsupported subpartitioning, only using LIST partitioning"))
+	tk.MustQuery(`show create table t`).Check(testkit.Rows("" +
+		"t CREATE TABLE `t` (\n" +
+		"  `a` int(11) DEFAULT NULL\n" +
+		") ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin\n" +
+		"PARTITION BY LIST (`a`)\n" +
+		"(PARTITION `pMax` VALUES IN (1,3,4))"))
+	tk.MustExec(`drop table t`)
+
+	tk.MustGetErrMsg(`create table t (a int) partition by hash (a) partitions 2 subpartition by key (a) subpartitions 2`, "[ddl:1500]It is only possible to mix RANGE/LIST partitioning with HASH/KEY partitioning for subpartitioning")
+	tk.MustGetErrMsg(`create table t (a int) partition by key (a) partitions 2 subpartition by hash (a) subpartitions 2`, "[ddl:1500]It is only possible to mix RANGE/LIST partitioning with HASH/KEY partitioning for subpartitioning")
+
+	tk.MustGetErrMsg(`CREATE TABLE t ( col1 INT NOT NULL, col2 INT NOT NULL, col3 INT NOT NULL, col4 INT NOT NULL, primary KEY (col1,col3) ) PARTITION BY HASH(col1) PARTITIONS 4 SUBPARTITION BY HASH(col3) SUBPARTITIONS 2`, "[ddl:1500]It is only possible to mix RANGE/LIST partitioning with HASH/KEY partitioning for subpartitioning")
+	tk.MustGetErrMsg(`CREATE TABLE t ( col1 INT NOT NULL, col2 INT NOT NULL, col3 INT NOT NULL, col4 INT NOT NULL, primary KEY (col1,col3) ) PARTITION BY KEY(col1) PARTITIONS 4 SUBPARTITION BY KEY(col3) SUBPARTITIONS 2`, "[ddl:1500]It is only possible to mix RANGE/LIST partitioning with HASH/KEY partitioning for subpartitioning")
+}
+
 func TestCreateTableWithRangeColumnPartition(t *testing.T) {
 	store := testkit.CreateMockStore(t, mockstore.WithDDLChecker())
 

ddl/partition.go

@@ -440,35 +440,32 @@ func buildTablePartitionInfo(ctx sessionctx.Context, s *ast.PartitionOptions, tb
 	var enable bool
 	switch s.Tp {
 	case model.PartitionTypeRange:
-		if s.Sub == nil {
-			enable = true
-		}
-	case model.PartitionTypeHash:
-		// Partition by hash is enabled by default.
-		// Note that linear hash is simply ignored, and creates non-linear hash.
-		if s.Linear {
-			ctx.GetSessionVars().StmtCtx.AppendWarning(dbterror.ErrUnsupportedCreatePartition.GenWithStack("LINEAR HASH is not supported, using non-linear HASH instead"))
-		}
-		if s.Sub == nil {
-			enable = true
+		enable = true
+	case model.PartitionTypeList:
+		// Partition by list is enabled only when tidb_enable_list_partition is 'ON'.
+		enable = ctx.GetSessionVars().EnableListTablePartition
+	case model.PartitionTypeHash, model.PartitionTypeKey:
+		// Partition by hash and key is enabled by default.
+		if s.Sub != nil {
+			// Subpartitioning only allowed with Range or List
+			return ast.ErrSubpartition
 		}
-	case model.PartitionTypeKey:
-		// Note that linear key is simply ignored, and creates non-linear hash.
+		// Note that linear hash is simply ignored, and creates non-linear hash/key.
 		if s.Linear {
-			ctx.GetSessionVars().StmtCtx.AppendWarning(dbterror.ErrUnsupportedCreatePartition.GenWithStack("LINEAR KEY is not supported, using non-linear KEY instead"))
+			ctx.GetSessionVars().StmtCtx.AppendWarning(dbterror.ErrUnsupportedCreatePartition.GenWithStack(fmt.Sprintf("LINEAR %s is not supported, using non-linear %s instead", s.Tp.String(), s.Tp.String())))
 		}
-		if s.Sub == nil && len(s.ColumnNames) != 0 {
+		if s.Tp == model.PartitionTypeHash || len(s.ColumnNames) != 0 {
 			enable = true
 		}
-	case model.PartitionTypeList:
-		// Partition by list is enabled only when tidb_enable_list_partition is 'ON'.
-		enable = ctx.GetSessionVars().EnableListTablePartition
 	}
 
 	if !enable {
 		ctx.GetSessionVars().StmtCtx.AppendWarning(dbterror.ErrUnsupportedCreatePartition.GenWithStack(fmt.Sprintf("Unsupported partition type %v, treat as normal table", s.Tp)))
 		return nil
 	}
+	if s.Sub != nil {
+		ctx.GetSessionVars().StmtCtx.AppendWarning(dbterror.ErrUnsupportedCreatePartition.GenWithStack(fmt.Sprintf("Unsupported subpartitioning, only using %v partitioning", s.Tp)))
+	}
 
 	pi := &model.PartitionInfo{
 		Type:   s.Tp,