fix(query): support last_row(tags) for super table query.

source/dnode/vnode/inc/vnode.h

@@ -138,7 +138,7 @@ void   *tsdbGetIdx(SMeta *pMeta);
 void   *tsdbGetIvtIdx(SMeta *pMeta);
 
 int32_t tsdbLastRowReaderOpen(void *pVnode, int32_t type, SArray *pTableIdList, int32_t numOfCols, void **pReader);
-int32_t tsdbRetrieveLastRow(void *pReader, SSDataBlock *pResBlock, const int32_t *slotIds);
+int32_t tsdbRetrieveLastRow(void *pReader, SSDataBlock *pResBlock, const int32_t *slotIds, SArray* pTableUids);
 int32_t tsdbLastrowReaderClose(void *pReader);
 int32_t tsdbGetTableSchema(SVnode *pVnode, int64_t uid, STSchema **pSchema, int64_t *suid);
 

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

@@ -104,7 +104,7 @@ int32_t tsdbLastrowReaderClose(void* pReader) {
   return TSDB_CODE_SUCCESS;
 }
 
-int32_t tsdbRetrieveLastRow(void* pReader, SSDataBlock* pResBlock, const int32_t* slotIds) {
+int32_t tsdbRetrieveLastRow(void* pReader, SSDataBlock* pResBlock, const int32_t* slotIds, SArray* pTableUidList) {
   if (pReader == NULL || pResBlock == NULL) {
     return TSDB_CODE_INVALID_PARA;
   }
@@ -141,14 +141,15 @@ int32_t tsdbRetrieveLastRow(void* pReader, SSDataBlock* pResBlock, const int32_t
         // appended or not.
         if (internalResult) {
           pResBlock->info.rows -= 1;
+          taosArrayClear(pTableUidList);
         }
 
         saveOneRow(pRow, pResBlock, pr, slotIds);
+        taosArrayPush(pTableUidList, &pKeyInfo->uid);
         internalResult = true;
         lastKey = pRow->ts;
       }
 
-      // taosMemoryFree(pRow);
       tsdbCacheRelease(lruCache, h);
     }
   } else if (pr->type == LASTROW_RETRIEVE_TYPE_ALL) {
@@ -171,6 +172,7 @@ int32_t tsdbRetrieveLastRow(void* pReader, SSDataBlock* pResBlock, const int32_t
       // tsdbCacheLastArray2Row(pLast, &pRow, pr->pSchema);
 
       saveOneRow(pRow, pResBlock, pr, slotIds);
+      taosArrayPush(pTableUidList, &pKeyInfo->uid);
 
       // taosMemoryFree(pRow);
       tsdbCacheRelease(lruCache, h);

source/libs/executor/inc/executorimpl.h

@@ -319,6 +319,7 @@ typedef struct SLastrowScanInfo {
   void           *pLastrowReader;
   SArray         *pColMatchInfo;
   int32_t        *pSlotIds;
+  SExprSupp       pseudoExprSup;
 } SLastrowScanInfo;
 
 typedef enum EStreamScanMode {
@@ -787,6 +788,8 @@ int32_t getBufferPgSize(int32_t rowSize, uint32_t* defaultPgsz, uint32_t* defaul
 
 void    doSetOperatorCompleted(SOperatorInfo* pOperator);
 void    doFilter(const SNode* pFilterNode, SSDataBlock* pBlock);
+int32_t addTagPseudoColumnData(SReadHandle* pHandle, SExprInfo* pPseudoExpr, int32_t numOfPseudoExpr,
+                               SSDataBlock* pBlock, const char* idStr);
 
 void    cleanupAggSup(SAggSupporter* pAggSup);
 void    destroyBasicOperatorInfo(void* param, int32_t numOfOutput);

source/libs/executor/src/cachescanoperator.c

@@ -45,20 +45,20 @@ SOperatorInfo* createLastrowScanOperator(SLastRowScanPhysiNode* pScanNode, SRead
   int32_t numOfCols = 0;
   pInfo->pColMatchInfo = extractColMatchInfo(pScanNode->pScanCols, pScanNode->node.pOutputDataBlockDesc, &numOfCols,
                                              COL_MATCH_FROM_COL_ID);
-  int32_t* pCols = taosMemoryMalloc(numOfCols * sizeof(int32_t));
-  for (int32_t i = 0; i < taosArrayGetSize(pInfo->pColMatchInfo); ++i) {
-    SColMatchInfo* pColMatch = taosArrayGet(pInfo->pColMatchInfo, i);
-    pCols[i] = pColMatch->colId;
-  }
-
   int32_t code = extractTargetSlotId(pInfo->pColMatchInfo, pTaskInfo, &pInfo->pSlotIds);
   if (code != TSDB_CODE_SUCCESS) {
     goto _error;
   }
 
-  tsdbLastRowReaderOpen(readHandle->vnode, LASTROW_RETRIEVE_TYPE_ALL, pTableList, taosArrayGetSize(pInfo->pColMatchInfo),
+  tsdbLastRowReaderOpen(readHandle->vnode, LASTROW_RETRIEVE_TYPE_SINGLE, pTableList, taosArrayGetSize(pInfo->pColMatchInfo),
                         &pInfo->pLastrowReader);
-  taosMemoryFree(pCols);
+
+  if (pScanNode->pScanPseudoCols != NULL) {
+    SExprSupp* pPseudoExpr = &pInfo->pseudoExprSup;
+
+    pPseudoExpr->pExprInfo = createExprInfo(pScanNode->pScanPseudoCols, NULL, &pPseudoExpr->numOfExprs);
+    pPseudoExpr->pCtx = createSqlFunctionCtx(pPseudoExpr->pExprInfo, pPseudoExpr->numOfExprs, &pPseudoExpr->rowEntryInfoOffset);
+  }
 
   pOperator->name = "LastrowScanOperator";
   pOperator->operatorType = QUERY_NODE_PHYSICAL_PLAN_LAST_ROW_SCAN;
@@ -100,7 +100,20 @@ SSDataBlock* doScanLastrow(SOperatorInfo* pOperator) {
   // check if it is a group by tbname
   if (size == taosArrayGetSize(pInfo->pTableList)) {
     blockDataCleanup(pInfo->pRes);
-    tsdbRetrieveLastRow(pInfo->pLastrowReader, pInfo->pRes, pInfo->pSlotIds);
+    SArray* pUidList = taosArrayInit(1, sizeof(tb_uid_t));
+    int32_t code = tsdbRetrieveLastRow(pInfo->pLastrowReader, pInfo->pRes, pInfo->pSlotIds, pUidList);
+    if (code != TSDB_CODE_SUCCESS)  {
+      longjmp(pTaskInfo->env, code);
+    }
+
+    // check for tag values
+    if (pInfo->pRes->info.rows > 0 && pInfo->pseudoExprSup.numOfExprs > 0) {
+      SExprSupp* pSup = &pInfo->pseudoExprSup;
+      pInfo->pRes->info.uid = *(tb_uid_t*) taosArrayGet(pUidList, 0);
+      addTagPseudoColumnData(&pInfo->readHandle, pSup->pExprInfo, pSup->numOfExprs, pInfo->pRes, GET_TASKID(pTaskInfo));
+    }
+
+    doSetOperatorCompleted(pOperator);
     return (pInfo->pRes->info.rows == 0) ? NULL : pInfo->pRes;
   } else {
     // todo fetch the result for each group

source/libs/executor/src/scanoperator.c

@@ -39,8 +39,6 @@ static int32_t buildSysDbTableInfo(const SSysTableScanInfo* pInfo, int32_t capac
 static int32_t buildDbTableInfoBlock(const SSDataBlock* p, const SSysTableMeta* pSysDbTableMeta, size_t size,
                                      const char* dbName);
 
-static int32_t addTagPseudoColumnData(SReadHandle* pHandle, SExprInfo* pPseudoExpr, int32_t numOfPseudoExpr,
-                                      SSDataBlock* pBlock, const char* idStr);
 static bool    processBlockWithProbability(const SSampleExecInfo* pInfo);
 
 bool processBlockWithProbability(const SSampleExecInfo* pInfo) {
@@ -320,8 +318,6 @@ int32_t addTagPseudoColumnData(SReadHandle* pHandle, SExprInfo* pPseudoExpr, int
     int32_t dstSlotId = pExpr->base.resSchema.slotId;
 
     SColumnInfoData* pColInfoData = taosArrayGet(pBlock->pDataBlock, dstSlotId);
-
-    colInfoDataEnsureCapacity(pColInfoData, pBlock->info.rows);
     colInfoDataCleanup(pColInfoData, pBlock->info.rows);
 
     int32_t functionId = pExpr->pExpr->_function.functionId;

source/libs/function/src/builtinsimpl.c

@@ -80,11 +80,12 @@ typedef struct STopBotRes {
 } STopBotRes;
 
 typedef struct SFirstLastRes {
-  bool hasResult;
+  bool    hasResult;
   // used for last_row function only, isNullRes in SResultRowEntry can not be passed to downstream.So,
   // this attribute is required
-  bool isNull;
+  bool    isNull;
   int32_t bytes;
+  int64_t ts;
   char    buf[];
 } SFirstLastRes;
 
@@ -2951,6 +2952,7 @@ int32_t firstLastFinalize(SqlFunctionCtx* pCtx, SSDataBlock* pBlock) {
 
   SFirstLastRes* pRes = GET_ROWCELL_INTERBUF(pResInfo);
   colDataAppend(pCol, pBlock->info.rows, pRes->buf, pRes->isNull||pResInfo->isNullRes);
+
   // handle selectivity
   STuplePos* pTuplePos = (STuplePos*)(pRes->buf + pRes->bytes + sizeof(TSKEY));
   setSelectivityValue(pCtx, pBlock, pTuplePos, pBlock->info.rows);
@@ -5988,7 +5990,7 @@ int32_t lastrowFunction(SqlFunctionCtx* pCtx) {
   SInputColumnInfoData* pInput = &pCtx->input;
   SColumnInfoData*      pInputCol = pInput->pData[0];
 
-  int32_t type = pInputCol->info.type;
+  int32_t type  = pInputCol->info.type;
   int32_t bytes = pInputCol->info.bytes;
 
   pInfo->bytes = bytes;
@@ -5999,7 +6001,7 @@ int32_t lastrowFunction(SqlFunctionCtx* pCtx) {
 
     char* data = colDataGetData(pInputCol, i);
     TSKEY cts = getRowPTs(pInput->pPTS, i);
-    if (pResInfo->numOfRes == 0 || *(TSKEY*)(pInfo->buf + bytes) < cts) {
+    if (pResInfo->numOfRes == 0 || pInfo->ts < cts) {
 
       if (colDataIsNull_s(pInputCol, i)) {
         pInfo->isNull = true;
@@ -6012,8 +6014,7 @@ int32_t lastrowFunction(SqlFunctionCtx* pCtx) {
         memcpy(pInfo->buf, data, bytes);
       }
 
-      *(TSKEY*)(pInfo->buf + bytes) = cts;
-
+      pInfo->ts = cts;
       pInfo->hasResult = true;
       pResInfo->numOfRes = 1;