feat(query): add avg function scalar version

TD-17344

include/libs/scalar/scalar.h

@@ -101,6 +101,7 @@ int32_t countScalarFunction(SScalarParam *pInput, int32_t inputNum, SScalarParam
 int32_t sumScalarFunction(SScalarParam *pInput, int32_t inputNum, SScalarParam *pOutput);
 int32_t minScalarFunction(SScalarParam *pInput, int32_t inputNum, SScalarParam *pOutput);
 int32_t maxScalarFunction(SScalarParam *pInput, int32_t inputNum, SScalarParam *pOutput);
+int32_t avgScalarFunction(SScalarParam *pInput, int32_t inputNum, SScalarParam *pOutput);
 int32_t stddevScalarFunction(SScalarParam *pInput, int32_t inputNum, SScalarParam *pOutput);
 
 #ifdef __cplusplus

source/libs/function/src/builtins.c

@@ -1999,6 +1999,7 @@ const SBuiltinFuncDefinition funcMgtBuiltins[] = {
     .getEnvFunc   = getAvgFuncEnv,
     .initFunc     = avgFunctionSetup,
     .processFunc  = avgFunction,
+    .sprocessFunc = avgScalarFunction,
     .finalizeFunc = avgFinalize,
     .invertFunc   = avgInvertFunction,
     .combineFunc  = avgCombine,

source/libs/scalar/src/sclfunc.c

@@ -1919,6 +1919,101 @@ int32_t maxScalarFunction(SScalarParam *pInput, int32_t inputNum, SScalarParam *
   return doMinMaxScalarFunction(pInput, inputNum, pOutput, false);
 }
 
+int32_t avgScalarFunction(SScalarParam *pInput, int32_t inputNum, SScalarParam *pOutput) {
+  SColumnInfoData *pInputData  = pInput->columnData;
+  SColumnInfoData *pOutputData = pOutput->columnData;
+
+  int32_t type = GET_PARAM_TYPE(pInput);
+  int64_t count = 0, sum = 0;
+  bool hasNull = false;
+
+  for (int32_t i = 0; i < pInput->numOfRows; ++i) {
+    if (colDataIsNull_s(pInputData, i)) {
+      hasNull = true;
+      break;
+    }
+
+    switch(type) {
+      case TSDB_DATA_TYPE_TINYINT: {
+        int8_t *in  = (int8_t *)pInputData->pData;
+        sum += in[i];
+        count++;
+        break;
+      }
+      case TSDB_DATA_TYPE_SMALLINT: {
+        int16_t *in  = (int16_t *)pInputData->pData;
+        sum += in[i];
+        count++;
+        break;
+      }
+      case TSDB_DATA_TYPE_INT: {
+        int32_t *in  = (int32_t *)pInputData->pData;
+        sum += in[i];
+        count++;
+        break;
+      }
+      case TSDB_DATA_TYPE_BIGINT: {
+        int64_t *in  = (int64_t *)pInputData->pData;
+        sum += in[i];
+        count++;
+        break;
+      }
+      case TSDB_DATA_TYPE_UTINYINT: {
+        uint8_t *in  = (uint8_t *)pInputData->pData;
+        sum += in[i];
+        count++;
+        break;
+      }
+      case TSDB_DATA_TYPE_USMALLINT: {
+        uint16_t *in  = (uint16_t *)pInputData->pData;
+        sum += in[i];
+        count++;
+        break;
+      }
+      case TSDB_DATA_TYPE_UINT: {
+        uint32_t *in  = (uint32_t *)pInputData->pData;
+        sum += in[i];
+        count++;
+        break;
+      }
+      case TSDB_DATA_TYPE_UBIGINT: {
+        uint64_t *in  = (uint64_t *)pInputData->pData;
+        sum += in[i];
+        count++;
+        break;
+      }
+      case TSDB_DATA_TYPE_FLOAT: {
+        float *in  = (float *)pInputData->pData;
+        sum += in[i];
+        count++;
+        break;
+      }
+      case TSDB_DATA_TYPE_DOUBLE: {
+        double *in  = (double *)pInputData->pData;
+        sum += in[i];
+        count++;
+        break;
+      }
+    }
+  }
+
+  double *out  = (double *)pOutputData->pData;
+  if (hasNull) {
+    colDataAppendNULL(pOutputData, 0);
+  } else {
+    if (IS_SIGNED_NUMERIC_TYPE(type)) {
+      *out = (int64_t)sum / (double)count;
+    } else if (IS_UNSIGNED_NUMERIC_TYPE(type)) {
+      *out = (uint64_t)sum / (double)count;
+    } else if (IS_FLOAT_TYPE(type)) {
+      *out = (double)sum / (double)count;
+    }
+  }
+
+  pOutput->numOfRows = 1;
+  return TSDB_CODE_SUCCESS;
+}
+
 int32_t stddevScalarFunction(SScalarParam *pInput, int32_t inputNum, SScalarParam *pOutput) {
   SColumnInfoData *pInputData  = pInput->columnData;
   SColumnInfoData *pOutputData = pOutput->columnData;
@@ -2031,3 +2126,4 @@ int32_t stddevScalarFunction(SScalarParam *pInput, int32_t inputNum, SScalarPara
   pOutput->numOfRows = 1;
   return TSDB_CODE_SUCCESS;
 }
+