// Copyright 2018 PingCAP, Inc. // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, // See the License for the specific language governing permissions and // limitations under the License. package aggfuncs import ( "unsafe" "github.com/pingcap/tidb/expression" "github.com/pingcap/tidb/sessionctx" "github.com/pingcap/tidb/util/chunk" ) // All the AggFunc implementations are listed here for navigation. var ( // All the AggFunc implementations for "COUNT" are listed here. _ AggFunc = (*countPartial)(nil) _ AggFunc = (*countOriginal4Int)(nil) _ AggFunc = (*countOriginal4Real)(nil) _ AggFunc = (*countOriginal4Decimal)(nil) _ AggFunc = (*countOriginal4Time)(nil) _ AggFunc = (*countOriginal4Duration)(nil) _ AggFunc = (*countOriginal4JSON)(nil) _ AggFunc = (*countOriginal4String)(nil) _ AggFunc = (*countOriginalWithDistinct4Int)(nil) _ AggFunc = (*countOriginalWithDistinct4Real)(nil) _ AggFunc = (*countOriginalWithDistinct4Decimal)(nil) _ AggFunc = (*countOriginalWithDistinct4Duration)(nil) _ AggFunc = (*countOriginalWithDistinct4String)(nil) _ AggFunc = (*countOriginalWithDistinct)(nil) // All the AggFunc implementations for "APPROX_COUNT_DISTINCT" are listed here. _ AggFunc = (*approxCountDistinctOriginal)(nil) _ AggFunc = (*approxCountDistinctPartial1)(nil) _ AggFunc = (*approxCountDistinctPartial2)(nil) _ AggFunc = (*approxCountDistinctFinal)(nil) // All the AggFunc implementations for "APPROX_PERCENTILE" are listed here. _ AggFunc = (*percentileOriginal4Int)(nil) _ AggFunc = (*percentileOriginal4Real)(nil) _ AggFunc = (*percentileOriginal4Decimal)(nil) // All the AggFunc implementations for "FIRSTROW" are listed here. _ AggFunc = (*firstRow4Decimal)(nil) _ AggFunc = (*firstRow4Int)(nil) _ AggFunc = (*firstRow4Time)(nil) _ AggFunc = (*firstRow4String)(nil) _ AggFunc = (*firstRow4Duration)(nil) _ AggFunc = (*firstRow4Float32)(nil) _ AggFunc = (*firstRow4Float64)(nil) _ AggFunc = (*firstRow4JSON)(nil) _ AggFunc = (*firstRow4Enum)(nil) _ AggFunc = (*firstRow4Set)(nil) // All the AggFunc implementations for "MAX"/"MIN" are listed here. _ AggFunc = (*maxMin4Int)(nil) _ AggFunc = (*maxMin4Uint)(nil) _ AggFunc = (*maxMin4Float32)(nil) _ AggFunc = (*maxMin4Float64)(nil) _ AggFunc = (*maxMin4Decimal)(nil) _ AggFunc = (*maxMin4String)(nil) _ AggFunc = (*maxMin4Duration)(nil) _ AggFunc = (*maxMin4JSON)(nil) _ AggFunc = (*maxMin4Enum)(nil) _ AggFunc = (*maxMin4Set)(nil) // All the AggFunc implementations for "AVG" are listed here. _ AggFunc = (*avgOriginal4Decimal)(nil) _ AggFunc = (*avgOriginal4DistinctDecimal)(nil) _ AggFunc = (*avgPartial4Decimal)(nil) _ AggFunc = (*avgOriginal4Float64)(nil) _ AggFunc = (*avgPartial4Float64)(nil) _ AggFunc = (*avgOriginal4DistinctFloat64)(nil) // All the AggFunc implementations for "SUM" are listed here. _ AggFunc = (*sum4DistinctFloat64)(nil) _ AggFunc = (*sum4DistinctDecimal)(nil) _ AggFunc = (*sum4Decimal)(nil) _ AggFunc = (*sum4Float64)(nil) // All the AggFunc implementations for "GROUP_CONCAT" are listed here. _ AggFunc = (*groupConcatDistinct)(nil) _ AggFunc = (*groupConcat)(nil) // All the AggFunc implementations for "BIT_OR" are listed here. _ AggFunc = (*bitOrUint64)(nil) // All the AggFunc implementations for "BIT_XOR" are listed here. _ AggFunc = (*bitXorUint64)(nil) // All the AggFunc implementations for "BIT_AND" are listed here. _ AggFunc = (*bitAndUint64)(nil) // All the AggFunc implementations for "JSON_OBJECTAGG" are listed here _ AggFunc = (*jsonObjectAgg)(nil) ) // PartialResult represents data structure to store the partial result for the // aggregate functions. Here we use unsafe.Pointer to allow the partial result // to be any type. type PartialResult unsafe.Pointer // AggFunc is the interface to evaluate the aggregate functions. type AggFunc interface { // AllocPartialResult allocates a specific data structure to store the // partial result, initializes it, and converts it to PartialResult to // return back. Aggregate operator implementation, no matter it's a hash // or stream, should hold this allocated PartialResult for the further // operations like: "ResetPartialResult", "UpdatePartialResult". AllocPartialResult() PartialResult // ResetPartialResult resets the partial result to the original state for a // specific aggregate function. It converts the input PartialResult to the // specific data structure which stores the partial result and then reset // every field to the proper original state. ResetPartialResult(pr PartialResult) // UpdatePartialResult updates the specific partial result for an aggregate // function using the input rows which all belonging to the same data group. // It converts the PartialResult to the specific data structure which stores // the partial result and then iterates on the input rows and update that // partial result according to the functionality and the state of the // aggregate function. UpdatePartialResult(sctx sessionctx.Context, rowsInGroup []chunk.Row, pr PartialResult) error // MergePartialResult will be called in the final phase when parallelly // executing. It converts the PartialResult `src`, `dst` to the same specific // data structure which stores the partial results, and then evaluate the // final result using the partial results as input values. MergePartialResult(sctx sessionctx.Context, src, dst PartialResult) error // AppendFinalResult2Chunk finalizes the partial result and append the // final result to the input chunk. Like other operations, it converts the // input PartialResult to the specific data structure which stores the // partial result and then calculates the final result and append that // final result to the chunk provided. AppendFinalResult2Chunk(sctx sessionctx.Context, pr PartialResult, chk *chunk.Chunk) error } type baseAggFunc struct { // args stores the input arguments for an aggregate function, we should // call arg.EvalXXX to get the actual input data for this function. args []expression.Expression // ordinal stores the ordinal of the columns in the output chunk, which is // used to append the final result of this function. ordinal int // frac stores digits of the fractional part of decimals, // which makes the decimal be the result of type inferring. frac int } func (*baseAggFunc) MergePartialResult(sctx sessionctx.Context, src, dst PartialResult) error { return nil } // SlidingWindowAggFunc is the interface to evaluate the aggregate functions using sliding window. type SlidingWindowAggFunc interface { // Slide evaluates the aggregate functions using a sliding window. The input // lastStart and lastEnd are the interval of the former sliding window, // shiftStart, shiftEnd mean the sliding window offset. Note that the input // PartialResult stores the intermediate result which will be used in the next // sliding window, ensure call ResetPartialResult after a frame are evaluated // completely. Slide(sctx sessionctx.Context, rows []chunk.Row, lastStart, lastEnd uint64, shiftStart, shiftEnd uint64, pr PartialResult) error }