diff --git a/include/libs/catalog/catalog.h b/include/libs/catalog/catalog.h
index 5019191fd195fb34ec8ff03bbbf5469dd81aa24e..0b45f715574f0621bd0d093e57fa8ac382d3597c 100644
--- a/include/libs/catalog/catalog.h
+++ b/include/libs/catalog/catalog.h
@@ -108,7 +108,7 @@ int32_t catalogUpdateVgroup(struct SCatalog* pCatalog, SVgroupListInfo* pVgroup)
 
 
 int32_t catalogGetDBVgroupVersion(struct SCatalog* pCatalog, const char* dbName, int32_t* version);
-int32_t catalogGetDBVgroup(struct SCatalog* pCatalog, void *pRpc, const SEpSet* pMgmtEps, const char* dbName, int32_t forceUpdate, SDBVgroupInfo* dbInfo);
+int32_t catalogGetDBVgroup(struct SCatalog* pCatalog, void *pRpc, const SEpSet* pMgmtEps, const char* dbName, int32_t forceUpdate, SDBVgroupInfo** dbInfo);
 int32_t catalogUpdateDBVgroup(struct SCatalog* pCatalog, const char* dbName, SDBVgroupInfo* dbInfo);
 
 
diff --git a/include/common/tmessage.h b/include/libs/query/query.h
similarity index 69%
rename from include/common/tmessage.h
rename to include/libs/query/query.h
index c728ee026eb05e111e5da67656763be2b128306c..866a69ed8e72378b7937d5ef46ef730c9ce4d5ee 100644
--- a/include/common/tmessage.h
+++ b/include/libs/query/query.h
@@ -13,20 +13,20 @@
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  */
 
-#ifndef _TD_COMMON_TMESSAGE_H_
-#define _TD_COMMON_TMESSAGE_H_
+#ifndef _TD_QUERY_H_
+#define _TD_QUERY_H_
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-extern int32_t (*tscBuildMsg[TSDB_MSG_TYPE_MAX])(void* input, char **msg, int32_t msgSize, int32_t *msgLen);
-extern int32_t (*tscProcessMsgRsp[TSDB_MSG_TYPE_MAX])(void* output, char *msg, int32_t msgSize);
 
+extern int32_t (*queryBuildMsg[TSDB_MSG_TYPE_MAX])(void* input, char **msg, int32_t msgSize, int32_t *msgLen);
+extern int32_t (*queryProcessMsgRsp[TSDB_MSG_TYPE_MAX])(void* output, char *msg, int32_t msgSize);
 
 
 #ifdef __cplusplus
 }
 #endif
 
-#endif /*_TD_COMMON_TMESSAGE_H_*/
+#endif /*_TD_QUERY_H_*/
diff --git a/source/common/inc/commonInt.h b/source/common/inc/commonInt.h
index 448600e22e0ab525dcd143d485603cee589b9a4b..e7d2dba95c7084ab061b82e9c2e81adb46953aad 100644
--- a/source/common/inc/commonInt.h
+++ b/source/common/inc/commonInt.h
@@ -21,17 +21,7 @@ extern "C" {
 #endif
 
 
-#include "tlog.h"
 
-extern int32_t cDebugFlag;
-
-#define tscFatal(...)  do { if (cDebugFlag & DEBUG_FATAL) { taosPrintLog("TSC FATAL ", cDebugFlag, __VA_ARGS__); }} while(0)
-#define tscError(...)  do { if (cDebugFlag & DEBUG_ERROR) { taosPrintLog("TSC ERROR ", cDebugFlag, __VA_ARGS__); }} while(0)
-#define tscWarn(...)   do { if (cDebugFlag & DEBUG_WARN)  { taosPrintLog("TSC WARN ", cDebugFlag, __VA_ARGS__); }}  while(0)
-#define tscInfo(...)   do { if (cDebugFlag & DEBUG_INFO)  { taosPrintLog("TSC ", cDebugFlag, __VA_ARGS__); }} while(0)
-#define tscDebug(...)  do { if (cDebugFlag & DEBUG_DEBUG) { taosPrintLog("TSC ", cDebugFlag, __VA_ARGS__); }} while(0)
-#define tscTrace(...)  do { if (cDebugFlag & DEBUG_TRACE) { taosPrintLog("TSC ", cDebugFlag, __VA_ARGS__); }} while(0)
-#define tscDebugL(...) do { if (cDebugFlag & DEBUG_DEBUG) { taosPrintLongString("TSC ", cDebugFlag, __VA_ARGS__); }} while(0)
 
 #ifdef __cplusplus
 }
diff --git a/source/libs/CMakeLists.txt b/source/libs/CMakeLists.txt
index 007bb1e967a930d994f973b313aeb8f8cc9574be..57a5023807507baa44261430056c6d6b885875f0 100644
--- a/source/libs/CMakeLists.txt
+++ b/source/libs/CMakeLists.txt
@@ -9,4 +9,5 @@ add_subdirectory(cache)
 add_subdirectory(catalog)
 add_subdirectory(executor)
 add_subdirectory(planner)
-add_subdirectory(function)
\ No newline at end of file
+add_subdirectory(function)
+add_subdirectory(query)
diff --git a/source/libs/catalog/CMakeLists.txt b/source/libs/catalog/CMakeLists.txt
index ff3e62700a7a9acc1a89bece0c5e288c67c014df..25c80d502afebab583b24a325aaadbb2731e042f 100644
--- a/source/libs/catalog/CMakeLists.txt
+++ b/source/libs/catalog/CMakeLists.txt
@@ -8,5 +8,5 @@ target_include_directories(
 
 target_link_libraries(
    catalog
-   PRIVATE os util common transport
-)
\ No newline at end of file
+   PRIVATE os util common transport query
+)
diff --git a/source/libs/catalog/src/catalog.c b/source/libs/catalog/src/catalog.c
index f4a4b01dab19a022722727a6f95a07d51a169f1e..b488ab8101c49d6d446fc625bb16e6ed564914a2 100644
--- a/source/libs/catalog/src/catalog.c
+++ b/source/libs/catalog/src/catalog.c
@@ -15,7 +15,7 @@
 
 #include "catalogInt.h"
 #include "trpc.h"
-#include "tmessage.h"
+#include "query.h"
 
 SCatalogMgmt ctgMgmt = {0};
 
@@ -24,7 +24,7 @@ int32_t ctgGetVgroupFromMnode(struct SCatalog* pCatalog, void *pRpc, const SEpSe
   SEpSet *pVnodeEpSet = NULL;
   int32_t msgLen = 0;
 
-  int32_t code = tscBuildMsg[TSDB_MSG_TYPE_VGROUP_LIST](NULL, &msg, 0, &msgLen);
+  int32_t code = queryBuildMsg[TSDB_MSG_TYPE_VGROUP_LIST](NULL, &msg, 0, &msgLen);
   if (code) {
     return code;
   }
@@ -39,7 +39,7 @@ int32_t ctgGetVgroupFromMnode(struct SCatalog* pCatalog, void *pRpc, const SEpSe
 
   rpcSendRecv(pRpc, (SEpSet*)pMgmtEps, &rpcMsg, &rpcRsp);
 
-  code = tscProcessMsgRsp[TSDB_MSG_TYPE_VGROUP_LIST](pVgroup, rpcRsp.pCont, rpcRsp.contLen);
+  code = queryProcessMsgRsp[TSDB_MSG_TYPE_VGROUP_LIST](pVgroup, rpcRsp.pCont, rpcRsp.contLen);
   if (code) {
     return code;
   }
@@ -63,7 +63,23 @@ int32_t ctgGetVgroupFromCache(SCatalog* pCatalog, SArray** pVgroupList, int32_t*
 }
 
 
+int32_t ctgGetDBVgroupFromCache(SCatalog* pCatalog, char *dbName, SDBVgroupInfo **dbInfo, int32_t *exist) {
+/*
+  if (NULL == pCatalog->dbCache.cache) {
+    *exist = 0;
+    return TSDB_CODE_SUCCESS;
+  }
+
+  taosHashGet(SHashObj * pHashObj, const void * key, size_t keyLen)
+
+  if (dbInfo) {
+    *pVgroupList = taosArrayDup(pCatalog->vgroupCache.arrayCache);
+  }
 
+  *exist = 1;
+*/  
+  return TSDB_CODE_SUCCESS;
+}
 
 
 int32_t catalogInit(SCatalogCfg *cfg) {
@@ -245,12 +261,41 @@ int32_t catalogGetDBVgroupVersion(struct SCatalog* pCatalog, const char* dbName,
   return TSDB_CODE_SUCCESS;
 }
 
-int32_t catalogGetDBVgroup(struct SCatalog* pCatalog, void *pRpc, const SEpSet* pMgmtEps, const char* dbName, int32_t forceUpdate, SDBVgroupInfo* dbInfo) {
+int32_t catalogUpdateDBVgroup(struct SCatalog* pCatalog, const char* dbName, SDBVgroupInfo* dbInfo) {
 
 }
 
-int32_t catalogUpdateDBVgroup(struct SCatalog* pCatalog, const char* dbName, SDBVgroupInfo* dbInfo) {
 
+
+
+int32_t catalogGetDBVgroup(struct SCatalog* pCatalog, void *pRpc, const SEpSet* pMgmtEps, const char* dbName, int32_t forceUpdate, SDBVgroupInfo** dbInfo) {
+  if (NULL == pCatalog || NULL == dbName || NULL == pRpc || NULL == pMgmtEps) {
+    return TSDB_CODE_CTG_INVALID_INPUT;
+  }
+
+/*
+  int32_t exist = 0;
+
+  if (0 == forceUpdate) {
+    CTG_ERR_RET(ctgGetDBVgroupFromCache(pCatalog, dbName, dbInfo, &exist));
+
+    if (exist) {
+      return TSDB_CODE_SUCCESS;
+    }
+  }
+
+  SDBVgroupInfo* newDbInfo = NULL;
+  
+  CTG_ERR_RET(ctgGetDBVgroupFromMnode(pCatalog, pRpc, pMgmtEps, dbName, &newDbInfo));
+
+  CTG_ERR_RET(catalogUpdateDBVgroup(pCatalog, dbName, newDbInfo));
+
+  if (dbInfo) {
+    *dbInfo = newDbInfo;
+  }
+*/
+
+  return TSDB_CODE_SUCCESS;
 }
 
 
@@ -265,7 +310,7 @@ int32_t catalogGetTableMetaFromMnode(struct SCatalog* pCatalog, void *pRpc, cons
   SEpSet *pVnodeEpSet = NULL;
   int32_t msgLen = 0;
 
-  int32_t code = tscBuildMsg[TSDB_MSG_TYPE_TABLE_META](&bInput, &msg, 0, &msgLen);
+  int32_t code = queryBuildMsg[TSDB_MSG_TYPE_TABLE_META](&bInput, &msg, 0, &msgLen);
   if (code) {
     return code;
   }
diff --git a/source/libs/query/CMakeLists.txt b/source/libs/query/CMakeLists.txt
new file mode 100644
index 0000000000000000000000000000000000000000..579a4b279c2509de12c3e0782103ec6e0229ba79
--- /dev/null
+++ b/source/libs/query/CMakeLists.txt
@@ -0,0 +1,12 @@
+aux_source_directory(src QUERY_SRC)
+add_library(query ${QUERY_SRC})
+target_include_directories(
+    query
+    PUBLIC "${CMAKE_SOURCE_DIR}/include/libs/query"
+    PRIVATE "${CMAKE_CURRENT_SOURCE_DIR}/inc"
+)
+
+target_link_libraries(
+   query
+   PRIVATE os util common transport
+)
diff --git a/source/libs/query/inc/queryInt.h b/source/libs/query/inc/queryInt.h
new file mode 100644
index 0000000000000000000000000000000000000000..f3204b378595a2bc83c988979807109e7bda79bc
--- /dev/null
+++ b/source/libs/query/inc/queryInt.h
@@ -0,0 +1,40 @@
+/*
+ * Copyright (c) 2019 TAOS Data, Inc. <jhtao@taosdata.com>
+ *
+ * This program is free software: you can use, redistribute, and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3
+ * or later ("AGPL"), as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef _TD_QUERY_INT_H_
+#define _TD_QUERY_INT_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+#include "tlog.h"
+
+extern int32_t qDebugFlag;
+
+#define qFatal(...)  do { if (qDebugFlag & DEBUG_FATAL) { taosPrintLog("QRY FATAL ", qDebugFlag, __VA_ARGS__); }} while(0)
+#define qError(...)  do { if (qDebugFlag & DEBUG_ERROR) { taosPrintLog("QRY ERROR ", qDebugFlag, __VA_ARGS__); }} while(0)
+#define qWarn(...)   do { if (qDebugFlag & DEBUG_WARN)  { taosPrintLog("QRY WARN ", qDebugFlag, __VA_ARGS__); }}  while(0)
+#define qInfo(...)   do { if (qDebugFlag & DEBUG_INFO)  { taosPrintLog("QRY ", qDebugFlag, __VA_ARGS__); }} while(0)
+#define qDebug(...)  do { if (qDebugFlag & DEBUG_DEBUG) { taosPrintLog("QRY ", qDebugFlag, __VA_ARGS__); }} while(0)
+#define qTrace(...)  do { if (qDebugFlag & DEBUG_TRACE) { taosPrintLog("QRY ", qDebugFlag, __VA_ARGS__); }} while(0)
+#define qDebugL(...) do { if (qDebugFlag & DEBUG_DEBUG) { taosPrintLongString("QRY ", qDebugFlag, __VA_ARGS__); }} while(0)
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /*_TD_QUERY_INT_H_*/
diff --git a/source/common/src/tmessage.c b/source/libs/query/src/querymsg.c
similarity index 86%
rename from source/common/src/tmessage.c
rename to source/libs/query/src/querymsg.c
index 07adf1d599469fa6b0bb9dad4e1f0348849c68fa..924878c872bd91f39b340aa91c5062ddfacf7a00 100644
--- a/source/common/src/tmessage.c
+++ b/source/libs/query/src/querymsg.c
@@ -14,15 +14,15 @@
  */
 
 #include "taosmsg.h"
-#include "commonint.h"
+#include "queryInt.h"
 
 
-int32_t (*tscBuildMsg[TSDB_MSG_TYPE_MAX])(void* input, char **msg, int32_t msgSize, int32_t *msgLen) = {0};
+int32_t (*queryBuildMsg[TSDB_MSG_TYPE_MAX])(void* input, char **msg, int32_t msgSize, int32_t *msgLen) = {0};
 
-int32_t (*tscProcessMsgRsp[TSDB_MSG_TYPE_MAX])(void* output, char *msg, int32_t msgSize) = {0};
+int32_t (*queryProcessMsgRsp[TSDB_MSG_TYPE_MAX])(void* output, char *msg, int32_t msgSize) = {0};
 
 
-int32_t tscBuildVgroupListReqMsg(void* input, char **msg, int32_t msgSize, int32_t *msgLen) {
+int32_t queryBuildVgroupListReqMsg(void* input, char **msg, int32_t msgSize, int32_t *msgLen) {
   if (NULL == msg || NULL == msgLen) {
     return TSDB_CODE_TSC_INVALID_INPUT;
   }
@@ -32,7 +32,7 @@ int32_t tscBuildVgroupListReqMsg(void* input, char **msg, int32_t msgSize, int32
   return TSDB_CODE_SUCCESS;
 }
 
-int32_t tscBuildTableMetaReqMsg(void* input, char **msg, int32_t msgSize, int32_t *msgLen) {
+int32_t queryBuildTableMetaReqMsg(void* input, char **msg, int32_t msgSize, int32_t *msgLen) {
   if (NULL == input || NULL == msg || NULL == msgLen) {
     return TSDB_CODE_TSC_INVALID_INPUT;
   }
@@ -61,7 +61,7 @@ int32_t tscBuildTableMetaReqMsg(void* input, char **msg, int32_t msgSize, int32_
 }
 
 
-int32_t tscProcessVgroupListRsp(void* output, char *msg, int32_t msgSize) {
+int32_t queryProcessVgroupListRsp(void* output, char *msg, int32_t msgSize) {
   if (NULL == output || NULL == msg || msgSize <= 0) {
     return TSDB_CODE_TSC_INVALID_INPUT;
   }
@@ -72,17 +72,17 @@ int32_t tscProcessVgroupListRsp(void* output, char *msg, int32_t msgSize) {
   pRsp->vgroupVersion = htonl(pRsp->vgroupVersion);
 
   if (pRsp->vgroupNum < 0) {
-    tscError("vgroup number[%d] in rsp is invalid", pRsp->vgroupNum);
+    qError("vgroup number[%d] in rsp is invalid", pRsp->vgroupNum);
     return TSDB_CODE_TSC_VALUE_OUT_OF_RANGE;
   }
 
   if (pRsp->vgroupVersion < 0) {
-    tscError("vgroup vgroupVersion[%d] in rsp is invalid", pRsp->vgroupVersion);
+    qError("vgroup vgroupVersion[%d] in rsp is invalid", pRsp->vgroupVersion);
     return TSDB_CODE_TSC_VALUE_OUT_OF_RANGE;
   }
 
   if (msgSize != (pRsp->vgroupNum * sizeof(pRsp->vgroupInfo[0]) + sizeof(*pRsp))) {
-    tscError("vgroup list msg size mis-match, msgSize:%d, vgroup number:%d", msgSize, pRsp->vgroupNum);
+    qError("vgroup list msg size mis-match, msgSize:%d, vgroup number:%d", msgSize, pRsp->vgroupNum);
     return TSDB_CODE_TSC_VALUE_OUT_OF_RANGE;
   }
 
@@ -104,12 +104,11 @@ int32_t tscProcessVgroupListRsp(void* output, char *msg, int32_t msgSize) {
 }
 
 void msgInit() {
-  tscBuildMsg[TSDB_MSG_TYPE_TABLE_META] = tscBuildTableMetaReqMsg;
-  tscBuildMsg[TSDB_MSG_TYPE_VGROUP_LIST] = tscBuildVgroupListReqMsg;
-
+  queryBuildMsg[TSDB_MSG_TYPE_TABLE_META] = queryBuildTableMetaReqMsg;
+  queryBuildMsg[TSDB_MSG_TYPE_VGROUP_LIST] = queryBuildVgroupListReqMsg;
 
   //tscProcessMsgRsp[TSDB_MSG_TYPE_TABLE_META] = tscProcessTableMetaRsp;
-  tscProcessMsgRsp[TSDB_MSG_TYPE_VGROUP_LIST] = tscProcessVgroupListRsp;
+  queryProcessMsgRsp[TSDB_MSG_TYPE_VGROUP_LIST] = queryProcessVgroupListRsp;
 
 /*
   tscBuildMsg[TSDB_SQL_SELECT] = tscBuildQueryMsg;