ddl: check the limitation when creating multi-valued index

ddl/index.go

@@ -81,7 +81,12 @@ func buildIndexColumns(ctx sessionctx.Context, columns []*model.ColumnInfo, inde
 		if err := checkIndexColumn(ctx, col, ip.Length); err != nil {
 			return nil, false, err
 		}
-		mvIndex = mvIndex || col.FieldType.IsArray()
+		if col.FieldType.IsArray() {
+			if mvIndex {
+				return nil, false, dbterror.ErrNotSupportedYet.GenWithStack("'more than one multi-valued key part per index'")
+			}
+			mvIndex = true
+		}
 		indexColLen := ip.Length
 		indexColumnLength, err := getIndexColumnLength(col, ip.Length)
 		if err != nil {

errors.toml

@@ -766,6 +766,11 @@ error = '''
 Incorrect usage of %s and %s
 '''
 
+["ddl:1235"]
+error = '''
+This version of TiDB doesn't yet support '%s'
+'''
+
 ["ddl:1246"]
 error = '''
 Converting column '%s' from %s to %s

expression/expression.go

@@ -998,7 +998,7 @@ func ColumnInfos2ColumnsAndNames(ctx sessionctx.Context, dbName, tblName model.C
 			if err != nil {
 				return nil, nil, errors.Trace(err)
 			}
-			e, err := RewriteAstExpr(ctx, expr, mockSchema, names, false)
+			e, err := RewriteAstExpr(ctx, expr, mockSchema, names, true)
 			if err != nil {
 				return nil, nil, errors.Trace(err)
 			}

expression/multi_valued_index_test.go

@@ -44,4 +44,15 @@ func TestMultiValuedIndexDDL(t *testing.T) {
 	tk.MustGetErrCode("create table t(j json, gc json as (cast(j->'$[*]' as unsigned array)));", errno.ErrNotSupportedYet)
 	tk.MustGetErrCode("create view v as select cast('[1,2,3]' as unsigned array);", errno.ErrNotSupportedYet)
 	tk.MustExec("create table t(a json, index idx((cast(a as signed array))));")
+
+	tk.MustExec("drop table t")
+	tk.MustGetErrCode("create table t(a json, b int, index idx(b, (cast(a as signed array)), (cast(a as signed array))));", errno.ErrNotSupportedYet)
+	tk.MustExec("create table t(a json, b int);")
+	tk.MustGetErrCode("create index idx on t (b, (cast(a as signed array)), (cast(a as signed array)))", errno.ErrNotSupportedYet)
+	tk.MustGetErrCode("alter table t add index idx(b, (cast(a as signed array)), (cast(a as signed array)))", errno.ErrNotSupportedYet)
+	tk.MustExec("create index idx1 on t (b, (cast(a as signed array)))")
+	tk.MustExec("alter table t add index idx2(b, (cast(a as signed array)))")
+
+	tk.MustExec("drop table t")
+	tk.MustExec("create table t(a json, b int, index idx3(b, (cast(a as signed array))));")
 }

util/dbterror/ddl_terror.go

@@ -429,4 +429,7 @@ var (
 	ErrTempTableNotAllowedWithTTL = ClassDDL.NewStd(mysql.ErrTempTableNotAllowedWithTTL)
 	// ErrUnsupportedTTLReferencedByFK returns when the TTL config is set for a table referenced by foreign key
 	ErrUnsupportedTTLReferencedByFK = ClassDDL.NewStd(mysql.ErrUnsupportedTTLReferencedByFK)
+
+	// ErrNotSupportedYet returns when tidb does not support this feature.
+	ErrNotSupportedYet = ClassDDL.NewStd(mysql.ErrNotSupportedYet)
 )