diff --git a/src/sql/engine/expr/ob_expr_merge_result_type.map b/src/sql/engine/expr/ob_expr_merge_result_type.map
index 9868d729f3..23e8f50512 100644
--- a/src/sql/engine/expr/ob_expr_merge_result_type.map
+++ b/src/sql/engine/expr/ob_expr_merge_result_type.map
@@ -1275,7 +1275,7 @@ static ObObjType MERGE_RESULT_TYPE[ObMaxType][ObMaxType] = {
         ObLongTextType,   /* CharType=>ObMediumTextType  */
         ObLongTextType,   /* CharType=>ObLongTextType  */
         ObVarcharType,    /* CharType=>ObBitType  */
-        ObCharType,       /* CharType=>ObEnumType  */
+        ObVarcharType,    /* CharType=>ObEnumType  */
         ObCharType,       /* CharType=>ObSetType  */
         ObMaxType,        /* CharType=>ObEnumInnerType  */
         ObMaxType,        /* CharType=>ObSetInnerType  */
@@ -1747,7 +1747,7 @@ static ObObjType MERGE_RESULT_TYPE[ObMaxType][ObMaxType] = {
         ObVarcharType,    /*ObEnumType=>TimeType  */
         ObVarcharType,    /*ObEnumType=>YearType  */
         ObVarcharType,    /*ObEnumType=>VarcharType  */
-        ObCharType,       /*ObEnumType=>CharType  */
+        ObVarcharType,    /*ObEnumType=>CharType  */
         ObVarcharType,    /*ObEnumType=>HexStringType  */
         ObMaxType,        /*ObEnumType=>ExtendType  */
         ObVarcharType,    /*ObEnumType=>UnknownType  */
@@ -3956,7 +3956,7 @@ static ObObjType MERGE_RESULT_TYPE_ORACLE[ObMaxType][ObMaxType] = {
         ObLongTextType,   /* CharType=>ObMediumTextType  */
         ObLongTextType,   /* CharType=>ObLongTextType  */
         ObVarcharType,    /* CharType=>ObBitType  */
-        ObCharType,       /* CharType=>ObEnumType  */
+        ObVarcharType,    /* CharType=>ObEnumType  */
         ObCharType,       /* CharType=>ObSetType  */
         ObMaxType,        /* CharType=>ObEnumInnerType  */
         ObMaxType,        /* CharType=>ObSetInnerType  */
@@ -4428,7 +4428,7 @@ static ObObjType MERGE_RESULT_TYPE_ORACLE[ObMaxType][ObMaxType] = {
         ObVarcharType,    /*ObEnumType=>TimeType  */
         ObVarcharType,    /*ObEnumType=>YearType  */
         ObVarcharType,    /*ObEnumType=>VarcharType  */
-        ObCharType,       /*ObEnumType=>CharType  */
+        ObVarcharType,    /*ObEnumType=>CharType  */
         ObVarcharType,    /*ObEnumType=>HexStringType  */
         ObMaxType,        /*ObEnumType=>ExtendType  */
         ObVarcharType,    /*ObEnumType=>UnknownType  */