diff --git a/src/gausskernel/optimizer/commands/variable.cpp b/src/gausskernel/optimizer/commands/variable.cpp
index bd1cb4a99..faf35fb4b 100644
--- a/src/gausskernel/optimizer/commands/variable.cpp
+++ b/src/gausskernel/optimizer/commands/variable.cpp
@@ -874,7 +874,7 @@ bool check_collation_connection(char** newval, void** extra, GucSource source)
     }
 
     Oid collid = get_collation_oid_with_lower_name(*newval, PG_INVALID_ENCODING);
-    if (!OidIsValid(collid)) {
+    if (!COLLATION_IN_B_FORMAT(collid)) {
         return false;
     }
 
diff --git a/src/test/regress/output/charset_connection_test.source b/src/test/regress/output/charset_connection_test.source
index 6478f6da4..583ea3664 100644
--- a/src/test/regress/output/charset_connection_test.source
+++ b/src/test/regress/output/charset_connection_test.source
@@ -293,16 +293,17 @@ show collation_connection;
 
 set names gbk;
 set names utf8 collate 'default';
+ERROR:  invalid value for parameter "collation_connection": "default"
 show character_set_connection;
  character_set_connection 
 --------------------------
- UTF8
+ GBK
 (1 row)
 
 show collation_connection;
  collation_connection 
 ----------------------
- default
+ gbk_chinese_ci
 (1 row)
 
 set names gbk;
@@ -321,6 +322,7 @@ show collation_connection;
 
 -- test charset = -1
 set collation_connection = 'C';
+ERROR:  invalid value for parameter "collation_connection": "C"
 show character_set_connection;
  character_set_connection 
 --------------------------
@@ -330,10 +332,11 @@ show character_set_connection;
 show collation_connection;
  collation_connection 
 ----------------------
- C
+ utf8mb4_general_ci
 (1 row)
 
 set collation_connection = 'default';
+ERROR:  invalid value for parameter "collation_connection": "default"
 show character_set_connection;
  character_set_connection 
 --------------------------
@@ -343,10 +346,11 @@ show character_set_connection;
 show collation_connection;
  collation_connection 
 ----------------------
- default
+ utf8mb4_general_ci
 (1 row)
 
 set collation_connection = 'POSIX';
+ERROR:  invalid value for parameter "collation_connection": "POSIX"
 show character_set_connection;
  character_set_connection 
 --------------------------
@@ -356,7 +360,7 @@ show character_set_connection;
 show collation_connection;
  collation_connection 
 ----------------------
- POSIX
+ utf8mb4_general_ci
 (1 row)
 
 \! @abs_bindir@/gs_guc reload -Z datanode -D @abs_srcdir@/tmp_check/datanode1 -c "b_format_behavior_compat_options=''" >/dev/null 2>&1