diff --git a/src/common/backend/parser/parse_expr.cpp b/src/common/backend/parser/parse_expr.cpp
index a05b870e5..82bc63ef0 100644
--- a/src/common/backend/parser/parse_expr.cpp
+++ b/src/common/backend/parser/parse_expr.cpp
@@ -1567,16 +1567,27 @@ static Node* transformUserVar(UserVar *uservar)
 
     GucUserParamsEntry *entry = (GucUserParamsEntry *)hash_search(u_sess->utils_cxt.set_user_params_htab,
         uservar->name, HASH_FIND, &found);
-
     if (!found) {
         /* return a null const */
         Const *nullValue = makeConst(UNKNOWNOID, -1, InvalidOid, -2, (Datum)0, true, false);
         return (Node *)nullValue;
     }
 
+    entry = (GucUserParamsEntry *)hash_search(u_sess->utils_cxt.set_user_params_htab, uservar->name, HASH_ENTER, &found);
+    if (entry == NULL) {
+        ereport(ERROR,
+            (errcode(ERRCODE_OUT_OF_MEMORY), errmsg("Failed to create user_defined entry due to out of memory")));
+    }
+
     UserVar *result = makeNode(UserVar);
+    Const *con = (Const *)copyObject(entry->value);
     result->name = uservar->name;
-    result->value = (Expr *)copyObject(entry->value);
+    result->value = (Expr *)con;
+
+    USE_MEMORY_CONTEXT(SESS_GET_MEM_CXT_GROUP(MEMORY_CONTEXT_CBB));
+    /* if uservar is parsed, set to true */
+    entry->value = (Const *)copyObject(con);
+    entry->isParse = true;
 
     return (Node *)result;
 }
diff --git a/src/common/backend/utils/misc/guc.cpp b/src/common/backend/utils/misc/guc.cpp
index 09edd6757..819ab5dde 100755
--- a/src/common/backend/utils/misc/guc.cpp
+++ b/src/common/backend/utils/misc/guc.cpp
@@ -12975,11 +12975,13 @@ void check_variable_value_info(const char* var_name, const Expr* var_expr)
 
     if (found) {
         entry->value = (Const *)copyObject((Const *)(var_expr));
+        entry->isParse = false;
     } else {
         errno_t errval = strncpy_s(entry->name, sizeof(entry->name), var_name, sizeof(entry->name) - 1);
         securec_check_errval(errval, , LOG);
 
         entry->value = (Const *)copyObject((Const *)(var_expr));
+        entry->isParse = false;
     }
 }
 
diff --git a/src/gausskernel/runtime/executor/execQual.cpp b/src/gausskernel/runtime/executor/execQual.cpp
index c50cebada..2b5429406 100644
--- a/src/gausskernel/runtime/executor/execQual.cpp
+++ b/src/gausskernel/runtime/executor/execQual.cpp
@@ -1083,7 +1083,22 @@ static Datum ExecEvalConst(ExprState* exprstate, ExprContext* econtext, bool* is
         GucUserParamsEntry *entry = (GucUserParamsEntry *)hash_search(u_sess->utils_cxt.set_user_params_htab, uservar->name, HASH_FIND, &found);
 
         /* if not found, return a null const */
-        con = found ? entry->value : makeConst(UNKNOWNOID, -1, InvalidOid, -2, (Datum)0, true, false);
+        if (found) {
+            if (entry->isParse) {
+                con = (Const *)uservar->value;
+            } else {
+                Node *node = coerce_type(NULL, (Node *)entry->value, entry->value->consttype, ((Const *)uservar->value)->consttype,
+                    -1, COERCION_IMPLICIT, COERCE_IMPLICIT_CAST, -1);
+                node = eval_const_expression_value(NULL, node, NULL);
+                if (nodeTag(node) != T_Const) {
+                    ereport(ERROR, (errcode(ERRCODE_INVALID_OPERATION),
+                        errmsg("The value of a user_defined variable must be convertible to a constant.")));
+                }
+                con = (Const *)node;
+            }
+        } else {
+            con = makeConst(UNKNOWNOID, -1, InvalidOid, -2, (Datum)0, true, false);
+        }
     } else if (IsA(exprstate->expr, SetVariableExpr)) {
         SetVariableExpr* setvar = (SetVariableExpr*)transformSetVariableExpr((SetVariableExpr*)exprstate->expr);
         con = (Const*)setvar->value;
diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h
index 6c8f885af..3fde019bc 100755
--- a/src/include/utils/guc.h
+++ b/src/include/utils/guc.h
@@ -191,6 +191,7 @@ typedef struct {
 typedef struct {
     char name[NAMEDATALEN];   /* user-defined name */
     Const *value;
+    bool isParse;
 } GucUserParamsEntry;
 
 #define GUC_QUALIFIER_SEPARATOR '.'
diff --git a/src/test/regress/input/set_user_defined_variables_test.source b/src/test/regress/input/set_user_defined_variables_test.source
index 06b051e56..94bca34e1 100644
--- a/src/test/regress/input/set_user_defined_variables_test.source
+++ b/src/test/regress/input/set_user_defined_variables_test.source
@@ -532,6 +532,28 @@ select @v1;
 set @ v1:=10;
 select @v1:=10;
 
+--DTS
+\c test_set
+set @v := 10;
+select @v + 666::numeric(10, 2), @v + 20::float;
+set @v = @v + 666::numeric(10, 2);
+select @v;
+
+set @v1 := 10, @v2 := 13.3;
+drop table if exists test_pro;
+create table test_pro(f1 int, f2 float);
+create or replace procedure pro_insert()
+as
+begin
+    insert into test_pro values(@v1 + 666::numeric(10, 2), @v2 + 20::float);
+end;
+/
+call pro_insert();
+select * from test_pro;
+set @v1 := 11, @v2 := 14.3;
+call pro_insert();
+select * from test_pro;
+
 \c test_set
 show enable_set_variable_b_format;
 set enable_set_variable_b_format = off;
diff --git a/src/test/regress/output/set_user_defined_variables_test.source b/src/test/regress/output/set_user_defined_variables_test.source
index 79af682f4..d2813f668 100644
--- a/src/test/regress/output/set_user_defined_variables_test.source
+++ b/src/test/regress/output/set_user_defined_variables_test.source
@@ -1125,6 +1125,57 @@ LINE 1: set @ v1:=10;
             ^
 select @v1:=10;
 ERROR:  user_defined variables cannot be set, such as @var_name := expr is not supported.
+--DTS
+\c test_set
+set @v := 10;
+select @v + 666::numeric(10, 2), @v + 20::float;
+ ?column? | ?column? 
+----------+----------
+   676.00 |       30
+(1 row)
+
+set @v = @v + 666::numeric(10, 2);
+select @v;
+ @v  
+-----
+ 676
+(1 row)
+
+set @v1 := 10, @v2 := 13.3;
+drop table if exists test_pro;
+create table test_pro(f1 int, f2 float);
+create or replace procedure pro_insert()
+as
+begin
+    insert into test_pro values(@v1 + 666::numeric(10, 2), @v2 + 20::float);
+end;
+/
+call pro_insert();
+ pro_insert 
+------------
+ 
+(1 row)
+
+select * from test_pro;
+ f1  |  f2  
+-----+------
+ 676 | 33.3
+(1 row)
+
+set @v1 := 11, @v2 := 14.3;
+call pro_insert();
+ pro_insert 
+------------
+ 
+(1 row)
+
+select * from test_pro;
+ f1  |  f2  
+-----+------
+ 676 | 33.3
+ 677 | 34.3
+(2 rows)
+
 \c test_set
 show enable_set_variable_b_format;
  enable_set_variable_b_format