Files
tidb/statistics/statscache_test.go

326 lines
11 KiB
Go

// 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_test
import (
"testing"
"github.com/juju/errors"
. "github.com/pingcap/check"
"github.com/pingcap/tidb"
"github.com/pingcap/tidb/domain"
"github.com/pingcap/tidb/kv"
"github.com/pingcap/tidb/model"
"github.com/pingcap/tidb/sessionctx/variable"
"github.com/pingcap/tidb/statistics"
"github.com/pingcap/tidb/util/testkit"
"github.com/pingcap/tidb/util/types"
)
func TestT(t *testing.T) {
TestingT(t)
}
var _ = Suite(&testStatsCacheSuite{})
type testStatsCacheSuite struct{}
func (s *testStatsCacheSuite) TestStatsCache(c *C) {
store, do, err := newStoreWithBootstrap()
c.Assert(err, IsNil)
defer store.Close()
testKit := testkit.NewTestKit(c, store)
testKit.MustExec("use test")
testKit.MustExec("create table t (c1 int, c2 int)")
testKit.MustExec("insert into t values(1, 2)")
is := do.InfoSchema()
tbl, err := is.TableByName(model.NewCIStr("test"), model.NewCIStr("t"))
c.Assert(err, IsNil)
tableInfo := tbl.Meta()
statsTbl := do.StatsHandle().GetTableStats(tableInfo.ID)
c.Assert(statsTbl.Pseudo, IsTrue)
testKit.MustExec("analyze table t")
statsTbl = do.StatsHandle().GetTableStats(tableInfo.ID)
c.Assert(statsTbl.Pseudo, IsFalse)
testKit.MustExec("create index idx_t on t(c1)")
is = do.InfoSchema()
statsTbl = do.StatsHandle().GetTableStats(tableInfo.ID)
// If index is build, but stats is not updated. statsTbl can also work.
c.Assert(statsTbl.Pseudo, IsFalse)
// But the added index will not work.
c.Assert(statsTbl.Indices[int64(1)], IsNil)
testKit.MustExec("analyze table t")
statsTbl = do.StatsHandle().GetTableStats(tableInfo.ID)
c.Assert(statsTbl.Pseudo, IsFalse)
// If the new schema drop a column, the table stats can still work.
testKit.MustExec("alter table t drop column c2")
is = do.InfoSchema()
do.StatsHandle().Clear()
do.StatsHandle().Update(is)
statsTbl = do.StatsHandle().GetTableStats(tableInfo.ID)
c.Assert(statsTbl.Pseudo, IsFalse)
// If the new schema add a column, the table stats can still work.
testKit.MustExec("alter table t add column c10 int")
is = do.InfoSchema()
do.StatsHandle().Clear()
do.StatsHandle().Update(is)
statsTbl = do.StatsHandle().GetTableStats(tableInfo.ID)
c.Assert(statsTbl.Pseudo, IsFalse)
}
func assertTableEqual(c *C, a *statistics.Table, b *statistics.Table) {
c.Assert(len(a.Columns), Equals, len(b.Columns))
for i := range a.Columns {
assertHistogramEqual(c, a.Columns[i].Histogram, b.Columns[i].Histogram)
}
c.Assert(len(a.Indices), Equals, len(b.Indices))
for i := range a.Indices {
assertHistogramEqual(c, a.Indices[i].Histogram, b.Indices[i].Histogram)
}
}
func assertHistogramEqual(c *C, a, b statistics.Histogram) {
c.Assert(a.ID, Equals, b.ID)
c.Assert(a.NDV, Equals, b.NDV)
c.Assert(len(a.Buckets), Equals, len(b.Buckets))
for j := 0; j < len(a.Buckets); j++ {
c.Assert(a.Buckets[j], DeepEquals, b.Buckets[j])
}
}
func (s *testStatsCacheSuite) TestStatsStoreAndLoad(c *C) {
store, do, err := newStoreWithBootstrap()
c.Assert(err, IsNil)
defer store.Close()
testKit := testkit.NewTestKit(c, store)
testKit.MustExec("use test")
testKit.MustExec("create table t (c1 int, c2 int)")
recordCount := 1000
for i := 0; i < recordCount; i++ {
testKit.MustExec("insert into t values (?, ?)", i, i+1)
}
testKit.MustExec("create index idx_t on t(c2)")
is := do.InfoSchema()
tbl, err := is.TableByName(model.NewCIStr("test"), model.NewCIStr("t"))
c.Assert(err, IsNil)
tableInfo := tbl.Meta()
testKit.MustExec("analyze table t")
statsTbl1 := do.StatsHandle().GetTableStats(tableInfo.ID)
do.StatsHandle().Clear()
do.StatsHandle().Update(is)
statsTbl2 := do.StatsHandle().GetTableStats(tableInfo.ID)
c.Assert(statsTbl2.Pseudo, IsFalse)
c.Assert(statsTbl2.Count, Equals, int64(recordCount))
assertTableEqual(c, statsTbl1, statsTbl2)
}
func (s *testStatsCacheSuite) TestEmptyTable(c *C) {
store, do, err := newStoreWithBootstrap()
c.Assert(err, IsNil)
defer store.Close()
testKit := testkit.NewTestKit(c, store)
testKit.MustExec("use test")
testKit.MustExec("create table t (c1 int, c2 int, key cc1(c1), key cc2(c2))")
testKit.MustExec("analyze table t")
is := do.InfoSchema()
tbl, err := is.TableByName(model.NewCIStr("test"), model.NewCIStr("t"))
c.Assert(err, IsNil)
tableInfo := tbl.Meta()
statsTbl := do.StatsHandle().GetTableStats(tableInfo.ID)
sc := new(variable.StatementContext)
count, err := statsTbl.ColumnGreaterRowCount(sc, types.NewDatum(1), tableInfo.Columns[0])
c.Assert(err, IsNil)
c.Assert(count, Equals, 0.0)
}
func (s *testStatsCacheSuite) TestColumnIDs(c *C) {
store, do, err := newStoreWithBootstrap()
c.Assert(err, IsNil)
defer store.Close()
testKit := testkit.NewTestKit(c, store)
testKit.MustExec("use test")
testKit.MustExec("create table t (c1 int, c2 int)")
testKit.MustExec("insert into t values(1, 2)")
testKit.MustExec("analyze table t")
is := do.InfoSchema()
tbl, err := is.TableByName(model.NewCIStr("test"), model.NewCIStr("t"))
c.Assert(err, IsNil)
tableInfo := tbl.Meta()
statsTbl := do.StatsHandle().GetTableStats(tableInfo.ID)
sc := new(variable.StatementContext)
count, err := statsTbl.ColumnLessRowCount(sc, types.NewDatum(2), tableInfo.Columns[0])
c.Assert(err, IsNil)
c.Assert(count, Equals, float64(1))
// Drop a column and the offset changed,
testKit.MustExec("alter table t drop column c1")
is = do.InfoSchema()
do.StatsHandle().Clear()
do.StatsHandle().Update(is)
tbl, err = is.TableByName(model.NewCIStr("test"), model.NewCIStr("t"))
c.Assert(err, IsNil)
tableInfo = tbl.Meta()
statsTbl = do.StatsHandle().GetTableStats(tableInfo.ID)
// At that time, we should get c2's stats instead of c1's.
count, err = statsTbl.ColumnLessRowCount(sc, types.NewDatum(2), tableInfo.Columns[0])
c.Assert(err, IsNil)
c.Assert(count, Equals, 0.0)
}
func (s *testStatsCacheSuite) TestVersion(c *C) {
store, do, err := newStoreWithBootstrap()
c.Assert(err, IsNil)
defer store.Close()
testKit := testkit.NewTestKit(c, store)
testKit.MustExec("use test")
testKit.MustExec("create table t1 (c1 int, c2 int)")
testKit.MustExec("analyze table t1")
is := do.InfoSchema()
tbl1, err := is.TableByName(model.NewCIStr("test"), model.NewCIStr("t1"))
c.Assert(err, IsNil)
tableInfo1 := tbl1.Meta()
h := statistics.NewHandle(testKit.Se)
testKit.MustExec("update mysql.stats_meta set version = 2 where table_id = ?", tableInfo1.ID)
h.Update(is)
c.Assert(h.LastVersion, Equals, uint64(2))
c.Assert(h.PrevLastVersion, Equals, uint64(0))
statsTbl1 := h.GetTableStats(tableInfo1.ID)
c.Assert(statsTbl1.Pseudo, IsFalse)
testKit.MustExec("create table t2 (c1 int, c2 int)")
testKit.MustExec("analyze table t2")
is = do.InfoSchema()
tbl2, err := is.TableByName(model.NewCIStr("test"), model.NewCIStr("t2"))
c.Assert(err, IsNil)
tableInfo2 := tbl2.Meta()
// A smaller version write, and we can still read it.
testKit.MustExec("update mysql.stats_meta set version = 1 where table_id = ?", tableInfo2.ID)
h.Update(is)
c.Assert(h.LastVersion, Equals, uint64(2))
c.Assert(h.PrevLastVersion, Equals, uint64(2))
statsTbl2 := h.GetTableStats(tableInfo2.ID)
c.Assert(statsTbl2.Pseudo, IsFalse)
testKit.MustExec("insert t1 values(1,2)")
testKit.MustExec("analyze table t1")
testKit.MustExec("update mysql.stats_meta set version = 4 where table_id = ?", tableInfo1.ID)
h.Update(is)
c.Assert(h.LastVersion, Equals, uint64(4))
c.Assert(h.PrevLastVersion, Equals, uint64(2))
statsTbl1 = h.GetTableStats(tableInfo1.ID)
c.Assert(statsTbl1.Count, Equals, int64(1))
testKit.MustExec("insert t2 values(1,2)")
testKit.MustExec("analyze table t2")
// A smaller version write, and we can still read it.
testKit.MustExec("update mysql.stats_meta set version = 3 where table_id = ?", tableInfo2.ID)
h.Update(is)
c.Assert(h.LastVersion, Equals, uint64(4))
c.Assert(h.PrevLastVersion, Equals, uint64(4))
statsTbl2 = h.GetTableStats(tableInfo2.ID)
c.Assert(statsTbl2.Count, Equals, int64(1))
testKit.MustExec("insert t2 values(1,2)")
testKit.MustExec("analyze table t2")
// A smaller version write, and we cannot read it. Because at this time, lastTwo Version is 4.
testKit.MustExec("update mysql.stats_meta set version = 3 where table_id = ?", tableInfo2.ID)
h.Update(is)
c.Assert(h.LastVersion, Equals, uint64(4))
c.Assert(h.PrevLastVersion, Equals, uint64(4))
statsTbl2 = h.GetTableStats(tableInfo2.ID)
c.Assert(statsTbl2.Count, Equals, int64(1))
// We add an index and analyze it, but DDL doesn't load.
testKit.MustExec("alter table t2 add column c3 int")
testKit.MustExec("analyze table t2")
// load it with old schema.
h.Update(is)
statsTbl2 = h.GetTableStats(tableInfo2.ID)
c.Assert(statsTbl2.Pseudo, IsFalse)
c.Assert(statsTbl2.Columns[int64(3)], IsNil)
// Next time DDL updated.
is = do.InfoSchema()
h.Update(is)
statsTbl2 = h.GetTableStats(tableInfo2.ID)
c.Assert(statsTbl2.Pseudo, IsFalse)
// We can read it without analyze again! Thanks for PrevLastVersion.
c.Assert(statsTbl2.Columns[int64(3)], NotNil)
}
func (s *testStatsCacheSuite) TestLoadHist(c *C) {
store, do, err := newStoreWithBootstrap()
c.Assert(err, IsNil)
defer store.Close()
testKit := testkit.NewTestKit(c, store)
testKit.MustExec("use test")
testKit.MustExec("create table t (c1 int, c2 int)")
h := do.StatsHandle()
err = h.HandleDDLEvent(<-h.DDLEventCh())
c.Assert(err, IsNil)
rowCount := 10
for i := 0; i < rowCount; i++ {
testKit.MustExec("insert into t values(1,2)")
}
testKit.MustExec("analyze table t")
is := do.InfoSchema()
tbl, err := is.TableByName(model.NewCIStr("test"), model.NewCIStr("t"))
c.Assert(err, IsNil)
tableInfo := tbl.Meta()
oldStatsTbl := h.GetTableStats(tableInfo.ID)
for i := 0; i < rowCount; i++ {
testKit.MustExec("insert into t values(1,2)")
}
h.DumpStatsDeltaToKV()
h.Update(do.InfoSchema())
newStatsTbl := h.GetTableStats(tableInfo.ID)
// The stats table is updated.
c.Assert(oldStatsTbl == newStatsTbl, IsFalse)
// The histograms is not updated.
for id, hist := range oldStatsTbl.Columns {
c.Assert(hist, Equals, newStatsTbl.Columns[id])
}
// Add column c3, we only update c3.
testKit.MustExec("alter table t add column c3 int")
err = h.HandleDDLEvent(<-h.DDLEventCh())
c.Assert(err, IsNil)
is = do.InfoSchema()
tbl, err = is.TableByName(model.NewCIStr("test"), model.NewCIStr("t"))
c.Assert(err, IsNil)
tableInfo = tbl.Meta()
h.Update(is)
newStatsTbl2 := h.GetTableStats(tableInfo.ID)
c.Assert(newStatsTbl2 == newStatsTbl, IsFalse)
// The histograms is not updated.
for id, hist := range newStatsTbl.Columns {
c.Assert(hist, Equals, newStatsTbl2.Columns[id])
}
c.Assert(newStatsTbl2.Columns[int64(3)].LastUpdateVersion, Greater, newStatsTbl2.Columns[int64(1)].LastUpdateVersion)
}
func newStoreWithBootstrap() (kv.Storage, *domain.Domain, error) {
store, err := tidb.NewStore(tidb.EngineGoLevelDBMemory)
if err != nil {
return nil, nil, errors.Trace(err)
}
do, err := tidb.BootstrapSession(store)
return store, do, errors.Trace(err)
}