// Copyright 2017 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 statistics import ( "time" . "github.com/pingcap/check" "github.com/pingcap/tidb/sessionctx/stmtctx" "github.com/pingcap/tidb/types" ) // extractSampleItemsDatums is for test purpose only to extract Datum slice // from SampleItem slice. func extractSampleItemsDatums(items []*SampleItem) []types.Datum { datums := make([]types.Datum, len(items)) for i, item := range items { datums[i] = item.Value } return datums } func (s *testStatisticsSuite) TestSketch(c *C) { sc := &stmtctx.StatementContext{TimeZone: time.Local} maxSize := 1000 sampleSketch, ndv, err := buildFMSketch(sc, extractSampleItemsDatums(s.samples), maxSize) c.Check(err, IsNil) c.Check(ndv, Equals, int64(6232)) rcSketch, ndv, err := buildFMSketch(sc, s.rc.(*recordSet).data, maxSize) c.Check(err, IsNil) c.Check(ndv, Equals, int64(73344)) pkSketch, ndv, err := buildFMSketch(sc, s.pk.(*recordSet).data, maxSize) c.Check(err, IsNil) c.Check(ndv, Equals, int64(100480)) sampleSketch.mergeFMSketch(pkSketch) sampleSketch.mergeFMSketch(rcSketch) c.Check(sampleSketch.NDV(), Equals, int64(100480)) maxSize = 2 sketch := NewFMSketch(maxSize) sketch.insertHashValue(1) sketch.insertHashValue(2) c.Check(len(sketch.hashset), Equals, maxSize) sketch.insertHashValue(4) c.Check(len(sketch.hashset), LessEqual, maxSize) } func (s *testStatisticsSuite) TestSketchProtoConversion(c *C) { sc := &stmtctx.StatementContext{TimeZone: time.Local} maxSize := 1000 sampleSketch, ndv, err := buildFMSketch(sc, extractSampleItemsDatums(s.samples), maxSize) c.Check(err, IsNil) c.Check(ndv, Equals, int64(6232)) p := FMSketchToProto(sampleSketch) f := FMSketchFromProto(p) c.Assert(sampleSketch.mask, Equals, f.mask) c.Assert(len(sampleSketch.hashset), Equals, len(f.hashset)) for val := range sampleSketch.hashset { c.Assert(f.hashset[val], IsTrue) } }