fix:[TS-3347]set ver to first version if version stored is smaller than first...

fix:[TS-3347]set ver to first version if version stored is smaller than first version in wal when subscribe db

include/libs/executor/executor.h

@@ -190,6 +190,8 @@ STimeWindow getAlignQueryTimeWindow(SInterval* pInterval, int32_t precision, int
 
 SArray* qGetQueriedTableListInfo(qTaskInfo_t tinfo);
 
+void verifyOffset(void *pWalReader, STqOffsetVal* pOffset);
+
 int32_t qStreamPrepareScan(qTaskInfo_t tinfo, STqOffsetVal* pOffset, int8_t subType);
 
 void qStreamSetOpen(qTaskInfo_t tinfo);

source/dnode/vnode/src/tq/tqUtil.c

@@ -246,6 +246,7 @@ static int32_t extractDataAndRspForDbStbSubscribe(STQ* pTq, STqHandle* pHandle,
 
 
   if (offset->type == TMQ_OFFSET__LOG) {
+    verifyOffset(pHandle->pWalReader, offset);
     int64_t fetchVer = offset->version + 1;
     pCkHead = taosMemoryMalloc(sizeof(SWalCkHead) + 2048);
     if (pCkHead == NULL) {

source/libs/executor/src/executor.c

@@ -1058,6 +1058,14 @@ void qStreamSetOpen(qTaskInfo_t tinfo) {
   pOperator->status = OP_NOT_OPENED;
 }
 
+void verifyOffset(void *pWalReader, STqOffsetVal* pOffset){
+  // if offset version is small than first version , let's seek to first version
+  int64_t firstVer = walGetFirstVer(((SWalReader*)pWalReader)->pWal);
+  if (pOffset->version + 1 < firstVer){
+    pOffset->version = firstVer - 1;
+  }
+}
+
 int32_t qStreamPrepareScan(qTaskInfo_t tinfo, STqOffsetVal* pOffset, int8_t subType) {
   SExecTaskInfo* pTaskInfo = (SExecTaskInfo*)tinfo;
   SOperatorInfo* pOperator = pTaskInfo->pRoot;
@@ -1083,12 +1091,7 @@ int32_t qStreamPrepareScan(qTaskInfo_t tinfo, STqOffsetVal* pOffset, int8_t subT
       tsdbReaderClose(pScanBaseInfo->dataReader);
       pScanBaseInfo->dataReader = NULL;
 
-      // let's seek to the next version in wal file
-      int64_t firstVer = walGetFirstVer(pInfo->tqReader->pWalReader->pWal);
-      if (pOffset->version + 1 < firstVer){
-        pOffset->version = firstVer - 1;
-      }
-
+      verifyOffset(pInfo->tqReader->pWalReader, pOffset);
       if (tqSeekVer(pInfo->tqReader, pOffset->version + 1, id) < 0) {
         qError("tqSeekVer failed ver:%" PRId64 ", %s", pOffset->version + 1, id);
         return -1;