diff --git a/examples/lua/build.sh b/examples/lua/build.sh
index 1e6fef632ceb828c9e0eca1a02dc4a6654906474..5e856f3e9ef0c18b309c1b6fa66f8c79b7dec2dd 100755
--- a/examples/lua/build.sh
+++ b/examples/lua/build.sh
@@ -4,5 +4,5 @@ if [ "$lua_header_installed" = "0" ]; then
   sudo apt install -y liblua5.3-dev
 fi
 
-gcc -std=c99 lua_connector.c -fPIC -shared -o luaconnector.so -Wall -ltaos -I/usr/include/lua5.3 -I../../include/client
+gcc -g -std=c99 lua_connector.c -fPIC -shared -o luaconnector.so -Wall -ltaos -I/usr/include/lua5.3 -I../../include/client
 
diff --git a/examples/lua/lua51/lua_connector51.c b/examples/lua/lua51/lua_connector51.c
index 8a9051dd0cb3da0fd82e752132d499a5935be758..c5ef9126a644cae83a730f5d39d501713aff9db5 100644
--- a/examples/lua/lua51/lua_connector51.c
+++ b/examples/lua/lua51/lua_connector51.c
@@ -67,7 +67,7 @@ static int l_connect(lua_State *L){
 
   taos = taos_connect(host, user,password,database, port);
   if (taos == NULL) {
-    printf("failed to connect server, reason:%s\n", taos_errstr(taos));
+    //printf("failed to connect server, reason:%s\n", taos_errstr(taos));
     
     lua_pushinteger(L, -1);
     lua_setfield(L, table_index, "code");
@@ -79,7 +79,7 @@ static int l_connect(lua_State *L){
     // printf("success to connect server\n");
     lua_pushinteger(L, 0);
     lua_setfield(L, table_index, "code");
-    lua_pushstring(L, taos_errstr(taos));
+    lua_pushstring(L, "success");
     lua_setfield(L, table_index, "error");    
     lua_pushlightuserdata(L,taos);
     lua_setfield(L, table_index, "conn");
diff --git a/examples/lua/lua_connector.c b/examples/lua/lua_connector.c
index c3d8bcb99548c787953cd27bcbb90b6c63ee5a4a..5d8226f2623f6451ef77b71dac1a6583ba6c460b 100644
--- a/examples/lua/lua_connector.c
+++ b/examples/lua/lua_connector.c
@@ -67,8 +67,7 @@ static int l_connect(lua_State *L){
 
   taos = taos_connect(host, user,password,database, port);
   if (taos == NULL) {
-    printf("failed to connect server, reason:%s\n", taos_errstr(taos));
-    
+//  printf("failed to connect server, reason:%s\n", taos_errstr(NULL));
     lua_pushinteger(L, -1);
     lua_setfield(L, table_index, "code");
     lua_pushstring(L, taos_errstr(taos));
@@ -79,7 +78,7 @@ static int l_connect(lua_State *L){
     // printf("success to connect server\n");
     lua_pushinteger(L, 0);
     lua_setfield(L, table_index, "code");
-    lua_pushstring(L, taos_errstr(taos));
+    lua_pushstring(L, "success");
     lua_setfield(L, table_index, "error");    
     lua_pushlightuserdata(L,taos);
     lua_setfield(L, table_index, "conn");