fix(query): fix memory leak.

source/dnode/vnode/inc/vnode.h

@@ -153,7 +153,7 @@ uint64_t getReaderMaxVersion(STsdbReader *pReader);
 
 int32_t tsdbCacherowsReaderOpen(void *pVnode, int32_t type, SArray *pTableIdList, int32_t numOfCols, void **pReader);
 int32_t tsdbRetrieveCacheRows(void *pReader, SSDataBlock *pResBlock, const int32_t *slotIds, SArray *pTableUids);
-int32_t tsdbCacherowsReaderClose(void *pReader);
+void*   tsdbCacherowsReaderClose(void *pReader);
 int32_t tsdbGetTableSchema(SVnode *pVnode, int64_t uid, STSchema **pSchema, int64_t *suid);
 
 void   tsdbCacheSetCapacity(SVnode *pVnode, size_t capacity);

source/dnode/vnode/src/tsdb/tsdbCacheRead.c

@@ -101,7 +101,7 @@ int32_t tsdbCacherowsReaderOpen(void* pVnode, int32_t type, SArray* pTableIdList
   return TSDB_CODE_SUCCESS;
 }
 
-int32_t tsdbCacherowsReaderClose(void* pReader) {
+void* tsdbCacherowsReaderClose(void* pReader) {
   SCacheRowsReader* p = pReader;
 
   if (p->pSchema != NULL) {
@@ -114,7 +114,7 @@ int32_t tsdbCacherowsReaderClose(void* pReader) {
   }
 
   taosMemoryFree(pReader);
-  return TSDB_CODE_SUCCESS;
+  return NULL;
 }
 
 static int32_t doExtractCacheRow(SCacheRowsReader* pr, SLRUCache* lruCache, uint64_t uid, STSRow** pRow,

source/libs/executor/src/cachescanoperator.c

@@ -207,7 +207,7 @@ SSDataBlock* doScanCache(SOperatorInfo* pOperator) {
           }
         }
 
-        tsdbCacherowsReaderClose(pInfo->pLastrowReader);
+        pInfo->pLastrowReader = tsdbCacherowsReaderClose(pInfo->pLastrowReader);
         return pInfo->pRes;
       }
     }
@@ -220,6 +220,15 @@ SSDataBlock* doScanCache(SOperatorInfo* pOperator) {
 void destroyLastrowScanOperator(void* param) {
   SLastrowScanInfo* pInfo = (SLastrowScanInfo*)param;
   blockDataDestroy(pInfo->pRes);
+  blockDataDestroy(pInfo->pBufferredRes);
+  taosMemoryFree(pInfo->pSlotIds);
+  taosArrayDestroy(pInfo->pUidList);
+  taosArrayDestroy(pInfo->pColMatchInfo);
+
+  if (pInfo->pLastrowReader != NULL) {
+    pInfo->pLastrowReader = tsdbCacherowsReaderClose(pInfo->pLastrowReader);
+  }
+
   taosMemoryFreeClear(param);
 }