diff --git a/src/sql/engine/expr/ob_expr_cast.cpp b/src/sql/engine/expr/ob_expr_cast.cpp
index 23b900ba4..424f4bd04 100644
--- a/src/sql/engine/expr/ob_expr_cast.cpp
+++ b/src/sql/engine/expr/ob_expr_cast.cpp
@@ -137,11 +137,24 @@ int ObExprCast::get_cast_string_len(ObExprResType& type1, ObExprResType& type2,
       case ObHexStringType:
       case ObRawType:
       case ObNVarchar2Type:
-      case ObNCharType: {
+      case ObNCharType:
+      case ObEnumType:
+      case ObSetType:
+      case ObEnumInnerType:
+      case ObSetInnerType:
+      case ObURowIDType:
+      case ObLobType: {
         res_len = type1.get_length();
         length_semantics = type1.get_length_semantics();
         break;
       }
+      case ObBitType: {
+        if (scale > 0) {
+          res_len = scale;
+        }
+        res_len = (res_len + 7) / 8;
+        break;
+      }
       default: {
         break;
       }
diff --git a/src/sql/engine/expr/ob_expr_cast.h b/src/sql/engine/expr/ob_expr_cast.h
index a402aec27..56ed7efe5 100644
--- a/src/sql/engine/expr/ob_expr_cast.h
+++ b/src/sql/engine/expr/ob_expr_cast.h
@@ -13,13 +13,14 @@
 #ifndef _OB_EXPR_CAST_H_
 #define _OB_EXPR_CAST_H_
 
+#include "common/object/ob_obj_type.h"
 #include "sql/engine/expr/ob_expr_operator.h"
 
 namespace oceanbase {
 namespace sql {
 
-// TODO::only support 26??
-static const int32_t CAST_STRING_DEFUALT_LENGTH[26] = {
+// The length of array need to be equal to the number of types defined at ObObjType
+static const int32_t CAST_STRING_DEFUALT_LENGTH[48] = {
     0,   // null
     4,   // tinyint
     6,   // smallint
@@ -45,9 +46,34 @@ static const int32_t CAST_STRING_DEFUALT_LENGTH[26] = {
     1,   // varchar
     1,   // char
     1,   // binary
-    0    // extend
+    0,   // extend
+    0,   // unknown
+    1,   // tinytext  text share default length with varchar
+    1,   // text
+    1,   // mediumtext
+    1,   // longtext
+    64,  // bit
+    1,   // enum
+    1,   // set
+    1,   // enuminner
+    1,   // setinner
+    25,  // timestampTZ  timestamp + time zone('+00:00')
+    25,  // timestampLTZ
+    19,  // timestampNano  timestamp + nanosecond scale
+    1,   // raw
+    7,   // intervalYM  yyyy-mm
+    19,  // intervalDS  ddd hh:mm:ss.fractionsecond(6)
+    12,  // numberfloat  same with float
+    1,   // nvarchar2  share default length with varchar
+    1,   // nchar  share default length with char
+    1,   // urowid
+    1,   // lob
+    0    // max, invalid type, or count of obj type
 };
 
+static_assert(common::ObMaxType + 1 == sizeof(CAST_STRING_DEFUALT_LENGTH) / sizeof(int32_t),
+    "Please keep the length of CAST_STRING_DEFUALT_LENGTH must equal to the number of types");
+
 class ObExprCast : public ObFuncExprOperator {
   OB_UNIS_VERSION_V(1);
   const static int32_t OB_LITERAL_MAX_INT_LEN = 21;