diff --git a/src/modules/http/inc/httpHandle.h b/src/modules/http/inc/httpHandle.h
index 1b746e15200e1dfa7f0b5dcfc0054120c94aee56..b10ced9c8d5351e6130490123ccfe5d4f1f9fe16 100644
--- a/src/modules/http/inc/httpHandle.h
+++ b/src/modules/http/inc/httpHandle.h
@@ -37,7 +37,7 @@
 #define HTTP_STEP_SIZE              1024    //http message get process step by step
 #define HTTP_MAX_URL                5       //http url stack size
 #define HTTP_METHOD_SCANNER_SIZE    7       //http method fp size
-#define HTTP_GC_TARGET_SIZE         128
+#define HTTP_GC_TARGET_SIZE         512
 
 #define HTTP_VERSION_10             0
 #define HTTP_VERSION_11             1
diff --git a/src/modules/http/src/gcJson.c b/src/modules/http/src/gcJson.c
index 0cb20ec7e1e4ab1608415cc88e622a4731711858..7f43cb9daba667052f1b3a19b3713a41aeeccba1 100644
--- a/src/modules/http/src/gcJson.c
+++ b/src/modules/http/src/gcJson.c
@@ -79,7 +79,9 @@ void gcStopQueryJson(HttpContext *pContext, HttpSqlCmd *cmd) {
   if (jsonBuf == NULL) return;
 
   // write end of target
-  gcWriteTargetEndJson(jsonBuf);
+  if (cmd->numOfRows != 0) {
+    gcWriteTargetEndJson(jsonBuf);
+  }
 }
 
 bool gcBuildQueryJson(HttpContext *pContext, HttpSqlCmd *cmd, TAOS_RES *result, int numOfRows) {
@@ -116,8 +118,8 @@ bool gcBuildQueryJson(HttpContext *pContext, HttpSqlCmd *cmd, TAOS_RES *result,
 
   if (groupFields == -1 && cmd->numOfRows == 0) {
     gcWriteTargetStartJson(jsonBuf, refIdBuffer, aliasBuffer);
-    cmd->numOfRows += numOfRows;
   }
+  cmd->numOfRows += numOfRows;
 
   for (int i = 0; i < numOfRows; ++i) {
     TAOS_ROW row = taos_fetch_row(result);
@@ -125,42 +127,42 @@ bool gcBuildQueryJson(HttpContext *pContext, HttpSqlCmd *cmd, TAOS_RES *result,
     // for group by
     if (groupFields != -1) {
       char target[HTTP_GC_TARGET_SIZE];
-
-      switch (fields[groupFields].type) {
-        case TSDB_DATA_TYPE_BOOL:
-        case TSDB_DATA_TYPE_TINYINT:
-          snprintf(target, HTTP_GC_TARGET_SIZE, "%s%d", aliasBuffer, *((int8_t *)row[groupFields]));
-          break;
-        case TSDB_DATA_TYPE_SMALLINT:
-          snprintf(target, HTTP_GC_TARGET_SIZE, "%s%d", aliasBuffer, *((int16_t *)row[groupFields]));
-          break;
-        case TSDB_DATA_TYPE_INT:
-          snprintf(target, HTTP_GC_TARGET_SIZE, "%s%d", aliasBuffer, *((int32_t *)row[groupFields]));
-          break;
-        case TSDB_DATA_TYPE_BIGINT:
-          snprintf(target, HTTP_GC_TARGET_SIZE, "%s%ld", aliasBuffer, *((int64_t *)row[groupFields]));
-          break;
-        case TSDB_DATA_TYPE_FLOAT:
-          snprintf(target, HTTP_GC_TARGET_SIZE, "%s%.5f", aliasBuffer, *((float *)row[groupFields]));
-          break;
-        case TSDB_DATA_TYPE_DOUBLE:
-          snprintf(target, HTTP_GC_TARGET_SIZE, "%s%.9f", aliasBuffer, *((double *)row[groupFields]));
-          break;
-        case TSDB_DATA_TYPE_BINARY:
-        case TSDB_DATA_TYPE_NCHAR:
-          snprintf(target, HTTP_GC_TARGET_SIZE, "%s%s", aliasBuffer, (char *)row[groupFields]);
-          break;
-        case TSDB_DATA_TYPE_TIMESTAMP:
-          if (precision == TSDB_TIME_PRECISION_MILLI) {
-            snprintf(target, HTTP_GC_TARGET_SIZE, "%s%ld", aliasBuffer, *((int64_t *) row[groupFields]));
-          } else {
-            snprintf(target, HTTP_GC_TARGET_SIZE, "%s%ld", aliasBuffer, *((int64_t *) row[groupFields]) / 1000);
-          }
-          break;
-        default:
-          snprintf(target, HTTP_GC_TARGET_SIZE, "%s%s", aliasBuffer, "invalidcol");
-          break;
+      int len;
+      len = snprintf(target,HTTP_GC_TARGET_SIZE,"%s{",aliasBuffer);
+      for (int i = dataFields + 1; i<num_fields; i++){
+          switch (fields[i].type) {
+          case TSDB_DATA_TYPE_BOOL:
+          case TSDB_DATA_TYPE_TINYINT:
+            len += snprintf(target + len, HTTP_GC_TARGET_SIZE - len, "%s:%d", fields[i].name, *((int8_t *)row[i]));
+            break;
+          case TSDB_DATA_TYPE_SMALLINT:
+            len += snprintf(target + len, HTTP_GC_TARGET_SIZE - len, "%s:%d", fields[i].name, *((int16_t *)row[i]));
+            break;
+          case TSDB_DATA_TYPE_INT:
+            len += snprintf(target + len, HTTP_GC_TARGET_SIZE - len, "%s:%d,", fields[i].name, *((int32_t *)row[i]));
+            break;
+          case TSDB_DATA_TYPE_BIGINT:
+            len += snprintf(target + len, HTTP_GC_TARGET_SIZE - len, "%s:%ld", fields[i].name, *((int64_t *)row[i]));
+            break;
+          case TSDB_DATA_TYPE_FLOAT:
+            len += snprintf(target + len, HTTP_GC_TARGET_SIZE - len, "%s:%.5f", fields[i].name, *((float *)row[i]));
+            break;
+          case TSDB_DATA_TYPE_DOUBLE:
+            len += snprintf(target + len, HTTP_GC_TARGET_SIZE - len, "%s:%.9f", fields[i].name, *((double *)row[i]));
+            break;
+          case TSDB_DATA_TYPE_BINARY:
+          case TSDB_DATA_TYPE_NCHAR:
+            len += snprintf(target + len, HTTP_GC_TARGET_SIZE - len, "%s:%s", fields[i].name, (char *)row[i]);
+            break;
+          default:
+            len += snprintf(target + len, HTTP_GC_TARGET_SIZE - len, "%s:%s", fields[i].name, "-");
+            break;
+        }
+        if(i < num_fields - 1 ){
+            len += snprintf(target + len, HTTP_GC_TARGET_SIZE - len, ", ");
+        }
       }
+      len += snprintf(target + len, HTTP_GC_TARGET_SIZE - len, "}");
 
       if (strcmp(target, targetBuffer) != 0) {
         // first target not write this section
@@ -217,7 +219,7 @@ bool gcBuildQueryJson(HttpContext *pContext, HttpSqlCmd *cmd, TAOS_RES *result,
           }
           break;
         default:
-          httpJsonString(jsonBuf, "invalidcol", 10);
+          httpJsonString(jsonBuf, "-", 1);
           break;
       }
     }