add precalculation interface

src/common/src/ttypes.c

@@ -304,7 +304,7 @@ tDataTypeDescriptor tDataTypeDesc[11] = {
   {TSDB_DATA_TYPE_FLOAT,     5, FLOAT_BYTES,  "FLOAT",     tsCompressFloat,     tsDecompressFloat,     getStatics_f},
   {TSDB_DATA_TYPE_DOUBLE,    6, DOUBLE_BYTES, "DOUBLE",    tsCompressDouble,    tsDecompressDouble,    getStatics_d},
   {TSDB_DATA_TYPE_BINARY,    6, 0,            "BINARY",    tsCompressString,    tsDecompressString,    NULL},
-  {TSDB_DATA_TYPE_TIMESTAMP, 9, LONG_BYTES,   "TIMESTAMP", tsCompressTimestamp, tsDecompressTimestamp, NULL},
+  {TSDB_DATA_TYPE_TIMESTAMP, 9, LONG_BYTES,   "TIMESTAMP", tsCompressTimestamp, tsDecompressTimestamp, getStatics_i64},
   {TSDB_DATA_TYPE_NCHAR,     5, 8,            "NCHAR",     tsCompressString,    tsDecompressString,    NULL},
 };
 

src/tsdb/inc/tsdbMain.h

@@ -495,12 +495,12 @@ void tsdbSetHelperTable(SRWHelper *pHelper, STable *pTable, STsdbRepo *pRepo);
 int  tsdbCloseHelperFile(SRWHelper *pHelper, bool hasError);
 
 // --------- For read operations
-int tsdbLoadCompIdx(SRWHelper *pHelper, void *target);
-int tsdbLoadCompInfo(SRWHelper *pHelper, void *target);
-int tsdbLoadCompData(SRWHelper *pHelper, SCompBlock *pCompBlock, void *target);
-int tsdbLoadBlockDataCols(SRWHelper *pHelper, SDataCols *pDataCols, int blkIdx, int16_t *colIds, int numOfColIds);
-int tsdbLoadBlockData(SRWHelper *pHelper, SCompBlock *pCompBlock, SDataCols *target);
-// void tsdbGetDataStatis(SRWHelper *pHelper, SDataStatis *pStatis, int numOfCols);
+int  tsdbLoadCompIdx(SRWHelper *pHelper, void *target);
+int  tsdbLoadCompInfo(SRWHelper *pHelper, void *target);
+int  tsdbLoadCompData(SRWHelper *pHelper, SCompBlock *pCompBlock, void *target);
+int  tsdbLoadBlockDataCols(SRWHelper *pHelper, SDataCols *pDataCols, int blkIdx, int16_t *colIds, int numOfColIds);
+int  tsdbLoadBlockData(SRWHelper *pHelper, SCompBlock *pCompBlock, SDataCols *target);
+void tsdbGetDataStatis(SRWHelper *pHelper, SDataStatis *pStatis, int numOfCols);
 
 // --------- For write operations
 int tsdbWriteDataBlock(SRWHelper *pHelper, SDataCols *pDataCols);

src/tsdb/src/tsdbRWHelper.c

@@ -543,6 +543,34 @@ int tsdbLoadCompData(SRWHelper *pHelper, SCompBlock *pCompBlock, void *target) {
   return 0;
 }
 
+void tsdbGetDataStatis(SRWHelper *pHelper, SDataStatis *pStatis, int numOfCols) {
+  SCompData *pCompData = pHelper->pCompData;
+
+  for (int i = 0, j = 0; i < numOfCols;) {
+    if (j >= pCompData->numOfCols) {
+      pStatis[i].numOfNull = -1;
+      i++;
+      continue;
+    }
+
+    if (pStatis[i].colId == pCompData->cols[j].colId) {
+      pStatis[i].sum = pCompData->cols[j].sum;
+      pStatis[i].max = pCompData->cols[j].max;
+      pStatis[i].min = pCompData->cols[j].min;
+      pStatis[i].maxIndex = pCompData->cols[j].maxIndex;
+      pStatis[i].minIndex = pCompData->cols[j].minIndex;
+      pStatis[i].numOfNull = pCompData->cols[j].numOfNull;
+      i++;
+      j++;
+    } else if (pStatis[i].colId < pCompData->cols[j].colId) {
+      pStatis[i].numOfNull = -1;
+      i++;
+    } else {
+      j++;
+    }
+  }
+}
+
 static int comparColIdCompCol(const void *arg1, const void *arg2) {
   return (*(int16_t *)arg1) - ((SCompCol *)arg2)->colId;
 }
@@ -748,7 +776,7 @@ static int tsdbWriteBlockToFile(SRWHelper *pHelper, SFile *pFile, SDataCols *pDa
 
     pCompCol->colId = pDataCol->colId;
     pCompCol->type = pDataCol->type;
-    if (tDataTypeDesc[pDataCol->type].getStatisFunc) {
+    if (tDataTypeDesc[pDataCol->type].getStatisFunc && ncol != 0) {
       (*tDataTypeDesc[pDataCol->type].getStatisFunc)(
           (TSKEY *)(pDataCols->cols[0].pData), pDataCol->pData, rowsToWrite, &(pCompCol->min), &(pCompCol->max),
           &(pCompCol->sum), &(pCompCol->minIndex), &(pCompCol->maxIndex), &(pCompCol->numOfNull));