use another way to fix

pkg/expression/chunk_executor.go

@@ -15,6 +15,7 @@
 package expression
 
 import (
+	"github.com/pingcap/errors"
 	"github.com/pingcap/tidb/pkg/parser/ast"
 	"github.com/pingcap/tidb/pkg/parser/mysql"
 	"github.com/pingcap/tidb/pkg/sessionctx"
@@ -179,7 +180,11 @@ func evalOneVec(ctx sessionctx.Context, expr Expression, input *chunk.Chunk, out
 				if result.IsNull(i) {
 					buf.AppendNull()
 				} else {
-					buf.AppendEnum(types.Enum{Value: 0, Name: result.GetString(i)})
+					enum, err := types.ParseEnumName(ft.GetElems(), result.GetString(i), ft.GetCollate())
+					if err != nil {
+						return errors.Errorf("Wrong enum value parsed during evaluation")
+					}
+					buf.AppendEnum(enum)
 				}
 			}
 			output.SetCol(colIdx, buf)
@@ -191,7 +196,11 @@ func evalOneVec(ctx sessionctx.Context, expr Expression, input *chunk.Chunk, out
 				if result.IsNull(i) {
 					buf.AppendNull()
 				} else {
-					buf.AppendSet(types.Set{Value: 0, Name: result.GetString(i)})
+					set, err := types.ParseSetName(ft.GetElems(), result.GetString(i), ft.GetCollate())
+					if err != nil {
+						return errors.Errorf("Wrong set value parsed during evaluation")
+					}
+					buf.AppendSet(set)
 				}
 			}
 			output.SetCol(colIdx, buf)

pkg/util/codec/codec.go

@@ -360,14 +360,11 @@ func encodeHashChunkRowIdx(typeCtx types.Context, row chunk.Row, tp *types.Field
 			b = unsafe.Slice((*byte)(unsafe.Pointer(&v)), sizeUint64)
 		} else {
 			flag = compactBytesFlag
-			enumVal := row.GetEnum(idx)
-			str := enumVal.Name
-			if str == "" {
-				enum, err := types.ParseEnumValue(tp.GetElems(), enumVal.Value)
-				if err == nil {
-					// str will be empty string if v out of definition of enum.
-					str = enum.Name
-				}
+			v := row.GetEnum(idx).Value
+			str := ""
+			if enum, err := types.ParseEnumValue(tp.GetElems(), v); err == nil {
+				// str will be empty string if v out of definition of enum.
+				str = enum.Name
 			}
 			b = ConvertByCollation(hack.Slice(str), tp)
 		}
@@ -579,14 +576,11 @@ func HashChunkSelected(typeCtx types.Context, h []hash.Hash64, chk *chunk.Chunk,
 				b = unsafe.Slice((*byte)(unsafe.Pointer(&v)), sizeUint64)
 			} else {
 				buf[0] = compactBytesFlag
-				enumVal := column.GetEnum(i)
-				str := enumVal.Name
-				if str == "" {
-					enum, err := types.ParseEnumValue(tp.GetElems(), enumVal.Value)
-					if err == nil {
-						// str will be empty string if v out of definition of enum.
-						str = enum.Name
-					}
+				v := column.GetEnum(i).Value
+				str := ""
+				if enum, err := types.ParseEnumValue(tp.GetElems(), v); err == nil {
+					// str will be empty string if v out of definition of enum.
+					str = enum.Name
 				}
 				b = ConvertByCollation(hack.Slice(str), tp)
 			}