diff --git a/contrib/dolphin/expected/test_set_charset.out b/contrib/dolphin/expected/test_set_charset.out
index b7f15c87ffa476524089d8b35b105b9b26ebc836..b1729c907483d0ba83da6ae59ab28859a1153416 100644
--- a/contrib/dolphin/expected/test_set_charset.out
+++ b/contrib/dolphin/expected/test_set_charset.out
@@ -62,5 +62,12 @@ show client_encoding;
  UTF8
 (1 row)
 
+set names binary;
+show client_encoding;
+ client_encoding 
+-----------------
+ SQL_ASCII
+(1 row)
+
 drop schema db_charset cascade;
 reset current_schema;
diff --git a/contrib/dolphin/plugin_parser/gram.y b/contrib/dolphin/plugin_parser/gram.y
index f78ff606bc26c4c0f608b8965b75dc0655538513..7c323ce19e8a0b1dec997444247012c22077d188 100644
--- a/contrib/dolphin/plugin_parser/gram.y
+++ b/contrib/dolphin/plugin_parser/gram.y
@@ -3590,6 +3590,7 @@ zone_value:
 
 opt_encoding:
 			SCONST									{ $$ = $1; }
+			| BINARY								{ $$ = (char*)$1; }
 			| normal_ident							{ $$ = $1; }
 			| DEFAULT								{ $$ = NULL; }
 			| /*EMPTY*/								{ $$ = NULL; }
diff --git a/contrib/dolphin/sql/test_set_charset.sql b/contrib/dolphin/sql/test_set_charset.sql
index 98c3716c39404fcf390a6cc17166fcd6dcc50b58..6076005cba3f9140791fcf405a7ec128dba7eda4 100644
--- a/contrib/dolphin/sql/test_set_charset.sql
+++ b/contrib/dolphin/sql/test_set_charset.sql
@@ -18,5 +18,7 @@ set names 'gbk';
 show client_encoding;
 set names default;
 show client_encoding;
+set names binary;
+show client_encoding;
 drop schema db_charset cascade;
 reset current_schema;