feat(query): add apercentile function

source/libs/function/inc/builtinsimpl.h

@@ -67,6 +67,11 @@ bool percentileFunctionSetup(SqlFunctionCtx *pCtx, SResultRowEntryInfo* pResultI
 int32_t percentileFunction(SqlFunctionCtx *pCtx);
 int32_t percentileFinalize(SqlFunctionCtx* pCtx, SSDataBlock* pBlock);
 
+bool getApercentileFuncEnv(struct SFunctionNode* pFunc, SFuncExecEnv* pEnv);
+bool apercentileFunctionSetup(SqlFunctionCtx *pCtx, SResultRowEntryInfo* pResultInfo);
+int32_t apercentileFunction(SqlFunctionCtx *pCtx);
+int32_t apercentileFinalize(SqlFunctionCtx* pCtx, SSDataBlock* pBlock);
+
 bool getDiffFuncEnv(struct SFunctionNode* pFunc, SFuncExecEnv* pEnv);
 bool diffFunctionSetup(SqlFunctionCtx *pCtx, SResultRowEntryInfo* pResInfo);
 int32_t diffFunction(SqlFunctionCtx *pCtx);

source/libs/function/src/builtins.c

@@ -815,10 +815,10 @@ const SBuiltinFuncDefinition funcMgtBuiltins[] = {
     .type = FUNCTION_TYPE_APERCENTILE,
     .classification = FUNC_MGT_AGG_FUNC,
     .translateFunc = translateApercentile,
-    .getEnvFunc   = getMinmaxFuncEnv,
+    .getEnvFunc   = getApercentileFuncEnv,
-    .initFunc     = minmaxFunctionSetup,
+    .initFunc     = apercentileFunctionSetup,
-    .processFunc  = maxFunction,
+    .processFunc  = apercentileFunction,
-    .finalizeFunc = functionFinalize
+    .finalizeFunc = apercentileFinalize
   },
   {
     .name = "top",

source/libs/function/src/builtinsimpl.c

@@ -20,6 +20,8 @@
 #include "taggfunction.h"
 #include "tcompare.h"
 #include "tdatablock.h"
+#include "tdigest.h"
+#include "thistogram.h"
 #include "tpercentile.h"
 
 #define HISTOGRAM_MAX_BINS_NUM   1000
@@ -95,6 +97,19 @@ typedef struct SPercentileInfo {
   int64_t     numOfElems;
 } SPercentileInfo;
 
+typedef struct SAPercentileInfo {
+  double result;
+  int8_t algo;
+  SHistogramInfo *pHisto;
+  TDigest *pTDigest;
+} SAPercentileInfo;
+
+typedef enum {
+  APERCT_ALGO_UNKNOWN = 0,
+  APERCT_ALGO_DEFAULT,
+  APERCT_ALGO_TDIGEST,
+} EAPerctAlgoType;
+
 typedef struct SDiffInfo {
   bool hasPrev;
   bool includeNull;
@@ -1790,6 +1805,131 @@ int32_t percentileFinalize(SqlFunctionCtx* pCtx, SSDataBlock* pBlock) {
   return functionFinalize(pCtx, pBlock);
 }
 
+bool getApercentileFuncEnv(SFunctionNode* pFunc, SFuncExecEnv* pEnv) {
+  int32_t bytesHist   = (int32_t)(sizeof(SAPercentileInfo) + sizeof(SHistogramInfo) + sizeof(SHistBin) * (MAX_HISTOGRAM_BIN + 1));
+  int32_t bytesDigest = (int32_t)(sizeof(SAPercentileInfo) + TDIGEST_SIZE(COMPRESSION));
+  pEnv->calcMemSize = MAX(bytesHist, bytesDigest);
+  return true;
+}
+
+static int8_t getApercentileAlgo(char *algoStr) {
+  int8_t algoType;
+  if (strcasecmp(algoStr, "default") == 0) {
+    algoType = APERCT_ALGO_DEFAULT;
+  } else if (strcasecmp(algoStr, "t-digest") == 0) {
+    algoType = APERCT_ALGO_TDIGEST;
+  } else {
+    algoType = APERCT_ALGO_UNKNOWN;
+  }
+
+  return algoType;
+}
+
+static void buildHistogramInfo(SAPercentileInfo* pInfo) {
+  pInfo->pHisto = (SHistogramInfo*) ((char*) pInfo + sizeof(SAPercentileInfo));
+  pInfo->pHisto->elems = (SHistBin*) ((char*)pInfo->pHisto + sizeof(SHistogramInfo));
+}
+
+bool apercentileFunctionSetup(SqlFunctionCtx* pCtx, SResultRowEntryInfo* pResultInfo) {
+  if (!functionSetup(pCtx, pResultInfo)) {
+    return false;
+  }
+
+  SAPercentileInfo* pInfo = GET_ROWCELL_INTERBUF(pResultInfo);
+  if (pCtx->numOfParams == 2) {
+    pInfo->algo = APERCT_ALGO_DEFAULT;
+  } else if (pCtx->numOfParams == 3) {
+    pInfo->algo = getApercentileAlgo(pCtx->param[2].param.pz);
+    if (pInfo->algo == APERCT_ALGO_UNKNOWN) {
+      return false;
+    }
+  }
+
+  char *tmp = (char *)pInfo + sizeof(SAPercentileInfo);
+  if (pInfo->algo == APERCT_ALGO_TDIGEST) {
+    pInfo->pTDigest = tdigestNewFrom(tmp, COMPRESSION);
+  } else {
+    buildHistogramInfo(pInfo);
+    pInfo->pHisto = tHistogramCreateFrom(tmp, MAX_HISTOGRAM_BIN);
+  }
+
+  return true;
+}
+
+int32_t apercentileFunction(SqlFunctionCtx* pCtx) {
+  int32_t              notNullElems = 0;
+  SResultRowEntryInfo* pResInfo = GET_RES_INFO(pCtx);
+
+  SInputColumnInfoData* pInput = &pCtx->input;
+  //SColumnDataAgg*       pAgg = pInput->pColumnDataAgg[0];
+
+  SColumnInfoData* pCol = pInput->pData[0];
+  int32_t          type = pCol->info.type;
+
+  SAPercentileInfo* pInfo = GET_ROWCELL_INTERBUF(pResInfo);
+
+  int32_t start = pInput->startRowIndex;
+  if (pInfo->algo == APERCT_ALGO_TDIGEST) {
+    for (int32_t i = start; i < pInput->numOfRows + start; ++i) {
+      if (colDataIsNull_f(pCol->nullbitmap, i)) {
+        continue;
+      }
+      notNullElems += 1;
+      char* data = colDataGetData(pCol, i);
+
+      double v = 0; // value
+      int64_t w = 1; // weigth
+      GET_TYPED_DATA(v, double, type, data);
+      tdigestAdd(pInfo->pTDigest, v, w);
+    }
+  } else {
+    for (int32_t i = start; i < pInput->numOfRows + start; ++i) {
+      if (colDataIsNull_f(pCol->nullbitmap, i)) {
+        continue;
+      }
+      notNullElems += 1;
+      char* data = colDataGetData(pCol, i);
+
+      double v = 0;
+      GET_TYPED_DATA(v, double, type, data);
+      tHistogramAdd(&pInfo->pHisto, v);
+    }
+  }
+
+  SET_VAL(pResInfo, notNullElems, 1);
+  return TSDB_CODE_SUCCESS;
+}
+
+int32_t apercentileFinalize(SqlFunctionCtx* pCtx, SSDataBlock* pBlock) {
+  SVariant* pVal    = &pCtx->param[1].param;
+  double    percent = (pVal->nType == TSDB_DATA_TYPE_BIGINT) ? pVal->i : pVal->d;
+
+  SResultRowEntryInfo* pResInfo = GET_RES_INFO(pCtx);
+  SAPercentileInfo*       pInfo = (SAPercentileInfo*)GET_ROWCELL_INTERBUF(pResInfo);
+
+  if (pInfo->algo == APERCT_ALGO_TDIGEST) {
+    if (pInfo->pTDigest->size > 0) {
+      pInfo->result = tdigestQuantile(pInfo->pTDigest, percent/100);
+    } else {  // no need to free
+      //setNull(pCtx->pOutput, pCtx->outputType, pCtx->outputBytes);
+      return TSDB_CODE_SUCCESS;
+    }
+  } else {
+    if (pInfo->pHisto->numOfElems > 0) {
+      double ratio[] = {percent};
+      double *res = tHistogramUniform(pInfo->pHisto, ratio, 1);
+      pInfo->result = *res;
+      //memcpy(pCtx->pOutput, res, sizeof(double));
+      taosMemoryFree(res);
+    } else {  // no need to free
+      //setNull(pCtx->pOutput, pCtx->outputType, pCtx->outputBytes);
+      return TSDB_CODE_SUCCESS;
+    }
+  }
+
+  return functionFinalize(pCtx, pBlock);
+}
+
 bool getFirstLastFuncEnv(SFunctionNode* pFunc, SFuncExecEnv* pEnv) {
   SColumnNode* pNode = nodesListGetNode(pFunc->pParameterList, 0);
   pEnv->calcMemSize = pNode->node.resType.bytes + sizeof(int64_t);
@@ -1802,8 +1942,6 @@ bool getSelectivityFuncEnv(SFunctionNode* pFunc, SFuncExecEnv* pEnv) {
   return true;
 }
 
-
-
 static FORCE_INLINE TSKEY getRowPTs(SColumnInfoData* pTsColInfo, int32_t rowIndex) {
   if (pTsColInfo == NULL) {
     return 0;