diff --git a/src/client/inc/tscBulkWrite.h b/src/client/inc/tscBulkWrite.h
index 6a5f805157fe51b6aea3f89e34896c05f90376d8..1bb3b8adbd7e5d31a2411379c2d2278346b73e1b 100644
--- a/src/client/inc/tscBulkWrite.h
+++ b/src/client/inc/tscBulkWrite.h
@@ -22,7 +22,6 @@ extern "C" {
 
 #include "tlist.h"
 #include "tarray.h"
-#include "tsclient.h"
 #include "tthread.h"
 
 typedef struct SAsyncBulkWriteDispatcher {
@@ -54,26 +53,8 @@ typedef struct SAsyncBulkWriteDispatcher {
   volatile bool shutdown;
 } SAsyncBulkWriteDispatcher;
 
-
-
-
-/**
- * Return the error result to the callback function, and release the sql object.
- *
- * @param pSql  the sql object.
- * @param code  the error code of the error result.
- */
-void tscReturnsError(SSqlObj* pSql, int code);
-
-/**
- * Proxy function to perform sequentially insert operation.
- *
- * @param param     the context of `batchResultCallback`.
- * @param tres      the result object.
- * @param code      the error code.
- */
-void batchResultCallback(void* param, TAOS_RES* tres, int32_t code);
-
+// forward declaration.
+typedef struct SSqlObj SSqlObj;
 /**
  * Merge the statements into single SSqlObj.
  *
@@ -84,14 +65,6 @@ void batchResultCallback(void* param, TAOS_RES* tres, int32_t code);
  */
 int32_t dispatcherStatementMerge(SArray* statements, SSqlObj** result);
 
-/**
- * Get the number of insertion row in the sql statement.
- *
- * @param pSql      the sql statement.
- * @return int32_t  the number of insertion row.
- */
-inline static int32_t statementGetInsertionRows(SSqlObj* pSql) { return pSql->cmd.insertParam.numOfRows; }
-
 /**
  * Poll all the SSqlObj* in the dispatcher's buffer.
  *
diff --git a/src/client/inc/tsclient.h b/src/client/inc/tsclient.h
index 5d1f08b1621273ea73cc407726fbdb9a6d5973b8..3c0a1a6a00e01d56050a0db8c5b45cf9734c398a 100644
--- a/src/client/inc/tsclient.h
+++ b/src/client/inc/tsclient.h
@@ -544,6 +544,9 @@ extern SHashObj  *tscVgroupMap;
 extern SHashObj  *tscTableMetaMap;
 extern SCacheObj *tscVgroupListBuf;
 
+// forward declaration.
+typedef struct SAsyncBulkWriteDispatcher SAsyncBulkWriteDispatcher;
+extern SAsyncBulkWriteDispatcher* tscDispatcher;
 extern int   tscObjRef;
 extern void *tscTmr;
 extern void *tscQhandle;
diff --git a/src/client/src/tscAsync.c b/src/client/src/tscAsync.c
index 7a0b9ae0a7405bc1d9de22927f748b088148f6eb..9049fb3a97d62385c4d3494b0063652924587074 100644
--- a/src/client/src/tscAsync.c
+++ b/src/client/src/tscAsync.c
@@ -37,26 +37,6 @@ static void tscAsyncQueryRowsForNextVnode(void *param, TAOS_RES *tres, int numOf
  */
 static void tscAsyncFetchRowsProxy(void *param, TAOS_RES *tres, int numOfRows);
 
-static SAsyncBulkWriteDispatcher* tscDispatcher;
-
-/**
- * Init the taosc async bulk write dispatcher.
- * 
- * @param batchSize  the batchSize of async bulk write dispatcher.
- * @param timeoutMs  the timeout of batching in milliseconds.
- */
-void tscInitAsyncDispatcher(int32_t batchSize, int32_t timeoutMs) {
-  tscDispatcher = createAsyncBulkWriteDispatcher(batchSize, timeoutMs);
-}
-
-/**
- * Destroy the taosc async bulk write dispatcher.
- */
-void tscDestroyAsyncDispatcher() {
-  destroyAsyncDispatcher(tscDispatcher);
-  tscDispatcher = NULL;
-}
-
 void doAsyncQuery(STscObj* pObj, SSqlObj* pSql, __async_cb_func_t fp, void* param, const char* sqlstr, size_t sqlLen) {
   SSqlCmd* pCmd = &pSql->cmd;
 
diff --git a/src/client/src/tscBulkWrite.c b/src/client/src/tscBulkWrite.c
index bacc2408cd320da93c001a312ef1575fd755e7fe..998a5ec0d40adaf9bb59155386074c43a24004ea 100644
--- a/src/client/src/tscBulkWrite.c
+++ b/src/client/src/tscBulkWrite.c
@@ -15,6 +15,7 @@
 
 #include "osAtomic.h"
 
+#include "tsclient.h"
 #include "tscBulkWrite.h"
 #include "tscSubquery.h"
 #include "tscLog.h"
@@ -35,7 +36,21 @@ typedef struct {
   Runnable runnable[];
 } BatchCallBackContext;
 
-void tscReturnsError(SSqlObj *pSql, int code) {
+/**
+ * Get the number of insertion row in the sql statement.
+ *
+ * @param pSql      the sql statement.
+ * @return int32_t  the number of insertion row.
+ */
+inline static int32_t statementGetInsertionRows(SSqlObj* pSql) { return pSql->cmd.insertParam.numOfRows; }
+
+/**
+ * Return the error result to the callback function, and release the sql object.
+ *
+ * @param pSql  the sql object.
+ * @param code  the error code of the error result.
+ */
+inline static void tscReturnsError(SSqlObj *pSql, int code) {
   if (pSql == NULL) {
     return;
   }
@@ -44,7 +59,14 @@ void tscReturnsError(SSqlObj *pSql, int code) {
   tscAsyncResultOnError(pSql);
 }
 
-void batchResultCallback(void* param, TAOS_RES* tres, int32_t code) {
+/**
+ * Proxy function to perform sequentially insert operation.
+ *
+ * @param param     the context of `batchResultCallback`.
+ * @param tres      the result object.
+ * @param code      the error code.
+ */
+static void batchResultCallback(void* param, TAOS_RES* tres, int32_t code) {
   BatchCallBackContext* context = param;
   SSqlObj*              res = tres;
 
diff --git a/src/client/src/tscSystem.c b/src/client/src/tscSystem.c
index 620525263f9a53cb5269812ddf2dbd71f5bd028d..de467896d66d94bb7f646b634291f84882a650af 100644
--- a/src/client/src/tscSystem.c
+++ b/src/client/src/tscSystem.c
@@ -26,6 +26,7 @@
 #include "tconfig.h"
 #include "ttimezone.h"
 #include "qScript.h"
+#include "tscBulkWrite.h"
 
 // global, not configurable
 #define TSC_VAR_NOT_RELEASE 1
@@ -49,6 +50,7 @@ void      *tscRpcCache;            // cache to keep rpc obj
 int32_t    tscNumOfThreads = 1;     // num of rpc threads
 char       tscLogFileName[] = "taoslog";
 int        tscLogFileNum = 10;
+SAsyncBulkWriteDispatcher* tscDispatcher = NULL;
 
 static pthread_mutex_t rpcObjMutex; // mutex to protect open the rpc obj concurrently
 static pthread_once_t  tscinit = PTHREAD_ONCE_INIT;
@@ -57,6 +59,24 @@ static pthread_mutex_t setConfMutex = PTHREAD_MUTEX_INITIALIZER;
 // pthread_once can not return result code, so result code is set to a global variable.
 static volatile int tscInitRes = 0;
 
+/**
+ * Init the taosc async bulk write dispatcher.
+ * 
+ * @param batchSize  the batchSize of async bulk write dispatcher.
+ * @param timeoutMs  the timeout of batching in milliseconds.
+ */
+void tscInitAsyncDispatcher(int32_t batchSize, int32_t timeoutMs) {
+  tscDispatcher = createAsyncBulkWriteDispatcher(batchSize, timeoutMs);
+}
+
+/**
+ * Destroy the taosc async bulk write dispatcher.
+ */
+void tscDestroyAsyncDispatcher() {
+  destroyAsyncDispatcher(tscDispatcher);
+  tscDispatcher = NULL;
+}
+
 void tscCheckDiskUsage(void *UNUSED_PARAM(para), void *UNUSED_PARAM(param)) {
   taosGetDisk();
   taosTmrReset(tscCheckDiskUsage, 20 * 1000, NULL, tscTmr, &tscCheckDiskUsageTmr);