Merge pull request #17095 from taosdata/feat/TS-1754-V26

Feat/TS-1754-V26 Support aggAlways config option to control count if zero row

src/client/src/tscUtil.c

@@ -1372,6 +1372,10 @@ void convertQueryResult(SSqlRes* pRes, SQueryInfo* pQueryInfo, uint64_t objId, b
   // set the correct result
   SSDataBlock* p = pQueryInfo->pQInfo->runtimeEnv.outputBuf;
   pRes->numOfRows = (p != NULL)? p->info.rows: 0;
+  bool completed = pRes->numOfRows == 0;
+  if (p && pRes->numOfRows == 0 && tsAggAlways) {
+    pRes->numOfRows = 1;
+  }
 
   if (pRes->code == TSDB_CODE_SUCCESS && pRes->numOfRows > 0) {
     tscCreateResPointerInfo(pRes, pQueryInfo);
@@ -1380,7 +1384,7 @@ void convertQueryResult(SSqlRes* pRes, SQueryInfo* pQueryInfo, uint64_t objId, b
 
   tscDebug("0x%"PRIx64" retrieve result in pRes, numOfRows:%d", objId, pRes->numOfRows);
   pRes->row = 0;
-  pRes->completed = (pRes->numOfRows == 0);
+  pRes->completed = completed;
 }
 
 /*

src/common/inc/tglobal.h

@@ -219,6 +219,7 @@ extern int32_t  cqDebugFlag;
 extern int32_t  debugFlag;
 
 extern int8_t tsClientMerge;
+extern int8_t tsAggAlways;
 
 // probe alive connection
 extern int32_t tsProbeSeconds;

src/common/src/tglobal.c

@@ -273,6 +273,7 @@ int32_t  cqDebugFlag = 131;
 int32_t  fsDebugFlag = 135;
 
 int8_t tsClientMerge = 0;
+int8_t tsAggAlways = 0; // Agg function always return value even if zero row 
 
 // probe alive connection
 int32_t tsProbeSeconds     =  5 * 60; // start probe link alive after tsProbeSeconds from starting query
@@ -1690,6 +1691,16 @@ static void doInitGlobalConfig(void) {
   cfg.unitType = TAOS_CFG_UTYPE_NONE;
   taosInitConfigOption(cfg);
 
+  cfg.option = "aggAlways";
+  cfg.ptr = &tsAggAlways;
+  cfg.valType = TAOS_CFG_VTYPE_INT8;
+  cfg.cfgType = TSDB_CFG_CTYPE_B_CONFIG | TSDB_CFG_CTYPE_B_SHOW | TSDB_CFG_CTYPE_B_CLIENT;
+  cfg.minValue = 0;
+  cfg.maxValue = 1;
+  cfg.ptrLength = 1;
+  cfg.unitType = TAOS_CFG_UTYPE_NONE;
+  taosInitConfigOption(cfg);
+
   // default JSON string type option "binary"/"nchar"
   cfg.option = "defaultJSONStrType";
   cfg.ptr = tsDefaultJSONStrType;

src/query/src/qAggMain.c

@@ -30,6 +30,7 @@
 #include "qUdf.h"
 #include "tcompare.h"
 #include "hashfunc.h"
+#include "tglobal.h"
 
 #define GET_INPUT_DATA_LIST(x) ((char *)((x)->pInput))
 #define GET_INPUT_DATA(x, y) (GET_INPUT_DATA_LIST(x) + (y) * (x)->inputBytes)

src/query/src/qExecutor.c

@@ -6625,7 +6625,7 @@ static SSDataBlock* doProjectOperation(void* param, bool* newgroup) {
   }
   copyTsColoum(pRes, pInfo->pCtx, pOperator->numOfOutput);
   clearNumOfRes(pInfo->pCtx, pOperator->numOfOutput);
-  return (pInfo->pRes->info.rows > 0) ? pInfo->pRes : NULL;
+  return pInfo->pRes;
 }
 
 static SSDataBlock* doLimit(void* param, bool* newgroup) {

src/query/src/queryMain.c

@@ -338,6 +338,45 @@ int32_t qRetrieveQueryResultInfo(qinfo_t qinfo, bool* buildRes, void* pRspContex
   return code;
 }
 
+bool qFitAlwaysValue(SQInfo * pQInfo) {
+  // must agg query
+  if (!pQInfo->query.simpleAgg)
+    return false;
+  
+  // must not include ts column
+  SSDataBlock* pBlock = pQInfo->runtimeEnv.outputBuf;
+  if (pBlock == NULL || pBlock->pDataBlock == NULL)
+    return false;
+
+  SColumnInfoData* pColInfoData = taosArrayGet(pBlock->pDataBlock, 0);
+  if (pColInfoData == NULL)
+    return false;
+  // must not first column is timestamp  
+  if (pColInfoData->info.type == TSDB_DATA_TYPE_TIMESTAMP)
+    return false;
+
+  // fit ok
+  return true;
+}
+
+bool doFillResultWithNull(SQInfo* pQInfo, char * data, size_t numOfRows) {
+  SQueryRuntimeEnv* pRuntimeEnv = &pQInfo->runtimeEnv;
+  SQueryAttr*       pQueryAttr = pRuntimeEnv->pQueryAttr;
+  SSDataBlock* pRes = pRuntimeEnv->outputBuf;
+
+  int32_t numOfCols = pQueryAttr->numOfOutput;
+  for (int32_t i = 0; i < numOfCols; ++i) {
+    int16_t functionId = pQueryAttr->pExpr1[i].base.functionId;
+    // col
+    SColumnInfoData* pCol = taosArrayGet(pRes->pDataBlock, i);
+    if (functionId != TSDB_FUNC_COUNT)
+      setNull(data, pCol->info.type, pCol->info.bytes);
+    data += pCol->info.bytes * numOfRows;
+  }
+
+  return true;
+}
+
 int32_t qDumpRetrieveResult(qinfo_t qinfo, SRetrieveTableRsp **pRsp, int32_t *contLen, bool* continueExec) {
   SQInfo *pQInfo = (SQInfo *)qinfo;
   int32_t compLen = 0;
@@ -350,6 +389,14 @@ int32_t qDumpRetrieveResult(qinfo_t qinfo, SRetrieveTableRsp **pRsp, int32_t *co
   SQueryRuntimeEnv* pRuntimeEnv = &pQInfo->runtimeEnv;
 
   int32_t s = GET_NUM_OF_RESULTS(pRuntimeEnv);
+  bool fillNull = false;
+  if (s == 0 && tsAggAlways) {
+    if (qFitAlwaysValue(pQInfo)) {
+      s = 1;
+      fillNull = true;
+    }
+  }
+
   size_t size = pQueryAttr->resultRowSize * s;
   size += sizeof(int32_t);
   size += sizeof(STableIdInfo) * taosHashGetSize(pRuntimeEnv->pTableRetrieveTsMap);
@@ -378,6 +425,9 @@ int32_t qDumpRetrieveResult(qinfo_t qinfo, SRetrieveTableRsp **pRsp, int32_t *co
   if (GET_NUM_OF_RESULTS(&(pQInfo->runtimeEnv)) > 0 && pQInfo->code == TSDB_CODE_SUCCESS) {
     doDumpQueryResult(pQInfo, (*pRsp)->data, (*pRsp)->compressed, &compLen);
   } else {
+    if (fillNull) {
+      doFillResultWithNull(pQInfo, (*pRsp)->data, 1);
+    }
     setQueryStatus(pRuntimeEnv, QUERY_OVER);
   }
 

src/util/inc/tconfig.h

@@ -20,7 +20,7 @@
 extern "C" {
 #endif
 
-#define TSDB_CFG_MAX_NUM    136
+#define TSDB_CFG_MAX_NUM    137
 #define TSDB_CFG_PRINT_LEN  23
 #define TSDB_CFG_OPTION_LEN 24
 #define TSDB_CFG_VALUE_LEN  41