diff --git a/src/tsdb/src/tsdbRWHelper.c b/src/tsdb/src/tsdbRWHelper.c
index b24731beda6dc32fc380830fff67f742408026a8..fc2592f732a53c7c1cd2b5b28f5e0f1d7b63e111 100644
--- a/src/tsdb/src/tsdbRWHelper.c
+++ b/src/tsdb/src/tsdbRWHelper.c
@@ -677,7 +677,7 @@ static int tsdbWriteBlockToFile(SRWHelper *pHelper, SFile *pFile, SDataCols *pDa
     nColsNotAllNull++;
   }
 
-  ASSERT(nColsNotAllNull > 0 && nColsNotAllNull <= pDataCols->numOfCols);
+  ASSERT(nColsNotAllNull >= 0 && nColsNotAllNull <= pDataCols->numOfCols);
 
   // Compress the data if neccessary
   int     tcol = 0;