stats: fix histogram boundaries overflow error (#7883) (#7944)

Author: alivxxx

statistics/feedback.go

@@ -243,20 +243,79 @@ type BucketFeedback struct {
 	upper    *types.Datum // The upper bound of the new bucket.
 }
 
+// outOfRange checks if the `val` is between `min` and `max`.
+func outOfRange(sc *stmtctx.StatementContext, min, max, val *types.Datum) (int, error) {
+	result, err := val.CompareDatum(sc, min)
+	if err != nil {
+		return 0, err
+	}
+	if result < 0 {
+		return result, nil
+	}
+	result, err = val.CompareDatum(sc, max)
+	if err != nil {
+		return 0, err
+	}
+	if result > 0 {
+		return result, nil
+	}
+	return 0, nil
+}
+
+// adjustFeedbackBoundaries adjust the feedback boundaries according to the `min` and `max`.
+// If the feedback has no intersection with `min` and `max`, we could just skip this feedback.
+func (f *feedback) adjustFeedbackBoundaries(sc *stmtctx.StatementContext, min, max *types.Datum) (bool, error) {
+	result, err := outOfRange(sc, min, max, f.lower)
+	if err != nil {
+		return false, err
+	}
+	if result > 0 {
+		return true, nil
+	}
+	if result < 0 {
+		f.lower = min
+	}
+	result, err = outOfRange(sc, min, max, f.upper)
+	if err != nil {
+		return false, err
+	}
+	if result < 0 {
+		return true, nil
+	}
+	if result > 0 {
+		f.upper = max
+	}
+	return false, nil
+}
+
 // buildBucketFeedback build the feedback for each bucket from the histogram feedback.
 func buildBucketFeedback(h *Histogram, feedback *QueryFeedback) (map[int]*BucketFeedback, int) {
 	bktID2FB := make(map[int]*BucketFeedback)
+	if len(feedback.feedback) == 0 {
+		return bktID2FB, 0
+	}
 	total := 0
-	for _, ran := range feedback.feedback {
-		idx, _ := h.Bounds.LowerBound(0, ran.lower)
+	sc := &stmtctx.StatementContext{TimeZone: time.UTC}
+	kind := feedback.feedback[0].lower.Kind()
+	min, max := getMinValue(kind, h.tp), getMaxValue(kind, h.tp)
+	for _, fb := range feedback.feedback {
+		skip, err := fb.adjustFeedbackBoundaries(sc, &min, &max)
+		if err != nil {
+			log.Debugf("adjust feedback boundaries failed, err: %v", errors.ErrorStack(err))
+			continue
+		}
+		if skip {
+			continue
+		}
+		idx, _ := h.Bounds.LowerBound(0, fb.lower)
 		bktIdx := 0
 		// The last bucket also stores the feedback that falls outside the upper bound.
 		if idx >= h.Bounds.NumRows()-2 {
 			bktIdx = h.Len() - 1
 		} else {
 			bktIdx = idx / 2
 			// Make sure that this feedback lies within the bucket.
-			if chunk.Compare(h.Bounds.GetRow(2*bktIdx+1), 0, ran.upper) < 0 {
+			if chunk.Compare(h.Bounds.GetRow(2*bktIdx+1), 0, fb.upper) < 0 {
 				continue
 			}
 		}
@@ -266,23 +325,23 @@ func buildBucketFeedback(h *Histogram, feedback *QueryFeedback) (map[int]*Bucket
 			bkt = &BucketFeedback{lower: h.GetLower(bktIdx), upper: h.GetUpper(bktIdx)}
 			bktID2FB[bktIdx] = bkt
 		}
-		bkt.feedback = append(bkt.feedback, ran)
+		bkt.feedback = append(bkt.feedback, fb)
 		// Update the bound if necessary.
-		res, err := bkt.lower.CompareDatum(nil, ran.lower)
+		res, err := bkt.lower.CompareDatum(nil, fb.lower)
 		if err != nil {
-			log.Debugf("compare datum %v with %v failed, err: %v", bkt.lower, ran.lower, errors.ErrorStack(err))
+			log.Debugf("compare datum %v with %v failed, err: %v", bkt.lower, fb.lower, errors.ErrorStack(err))
 			continue
 		}
 		if res > 0 {
-			bkt.lower = ran.lower
+			bkt.lower = fb.lower
 		}
-		res, err = bkt.upper.CompareDatum(nil, ran.upper)
+		res, err = bkt.upper.CompareDatum(nil, fb.upper)
 		if err != nil {
-			log.Debugf("compare datum %v with %v failed, err: %v", bkt.upper, ran.upper, errors.ErrorStack(err))
+			log.Debugf("compare datum %v with %v failed, err: %v", bkt.upper, fb.upper, errors.ErrorStack(err))
 			continue
 		}
 		if res < 0 {
-			bkt.upper = ran.upper
+			bkt.upper = fb.upper
 		}
 	}
 	return bktID2FB, total
@@ -528,7 +587,12 @@ func splitBuckets(h *Histogram, feedback *QueryFeedback) ([]bucket, []bool, int6
 func UpdateHistogram(h *Histogram, feedback *QueryFeedback) *Histogram {
 	buckets, isNewBuckets, totalCount := splitBuckets(h, feedback)
 	buckets = mergeBuckets(buckets, isNewBuckets, float64(totalCount))
-	return buildNewHistogram(h, buckets)
+	hist := buildNewHistogram(h, buckets)
+	// Update the NDV of primary key column.
+	if feedback.tp == pkType {
+		hist.NDV = int64(hist.totalRowCount())
+	}
+	return hist
 }
 
 // UpdateCMSketch updates the CMSketch by feedback.
@@ -1077,13 +1141,13 @@ func supportColumnType(k byte) bool {
 func getMaxValue(k byte, ft *types.FieldType) (max types.Datum) {
 	switch k {
 	case types.KindInt64:
-		max.SetInt64(math.MaxInt64)
+		max.SetInt64(types.SignedUpperBound[ft.Tp])
 	case types.KindUint64:
-		max.SetUint64(math.MaxUint64)
+		max.SetUint64(types.UnsignedUpperBound[ft.Tp])
 	case types.KindFloat32:
-		max.SetFloat32(math.MaxFloat32)
+		max.SetFloat32(float32(types.GetMaxFloat(ft.Flen, ft.Decimal)))
 	case types.KindFloat64:
-		max.SetFloat64(math.MaxFloat64)
+		max.SetFloat64(types.GetMaxFloat(ft.Flen, ft.Decimal))
 	case types.KindString, types.KindBytes:
 		val := types.MaxValueDatum()
 		bytes, err := codec.EncodeKey(nil, nil, val)
@@ -1093,7 +1157,7 @@ func getMaxValue(k byte, ft *types.FieldType) (max types.Datum) {
 		}
 		max.SetBytes(bytes)
 	case types.KindMysqlDecimal:
-		max.SetMysqlDecimal(types.NewMaxOrMinDec(false, mysql.MaxDecimalWidth, 0))
+		max.SetMysqlDecimal(types.NewMaxOrMinDec(false, ft.Flen, ft.Decimal))
 	case types.KindMysqlDuration:
 		max.SetMysqlDuration(types.Duration{Duration: math.MaxInt64})
 	case types.KindMysqlTime:
@@ -1109,13 +1173,13 @@ func getMaxValue(k byte, ft *types.FieldType) (max types.Datum) {
 func getMinValue(k byte, ft *types.FieldType) (min types.Datum) {
 	switch k {
 	case types.KindInt64:
-		min.SetInt64(math.MinInt64)
+		min.SetInt64(types.SignedLowerBound[ft.Tp])
 	case types.KindUint64:
 		min.SetUint64(0)
 	case types.KindFloat32:
-		min.SetFloat32(-math.MaxFloat32)
+		min.SetFloat32(float32(-types.GetMaxFloat(ft.Flen, ft.Decimal)))
 	case types.KindFloat64:
-		min.SetFloat64(-math.MaxFloat64)
+		min.SetFloat64(-types.GetMaxFloat(ft.Flen, ft.Decimal))
 	case types.KindString, types.KindBytes:
 		val := types.MinNotNullDatum()
 		bytes, err := codec.EncodeKey(nil, nil, val)
@@ -1125,7 +1189,7 @@ func getMinValue(k byte, ft *types.FieldType) (min types.Datum) {
 		}
 		min.SetBytes(bytes)
 	case types.KindMysqlDecimal:
-		min.SetMysqlDecimal(types.NewMaxOrMinDec(true, mysql.MaxDecimalWidth, 0))
+		min.SetMysqlDecimal(types.NewMaxOrMinDec(true, ft.Flen, ft.Decimal))
 	case types.KindMysqlDuration:
 		min.SetMysqlDuration(types.Duration{Duration: math.MinInt64})
 	case types.KindMysqlTime:

statistics/feedback_test.go

@@ -70,7 +70,7 @@ func (s *testFeedbackSuite) TestUpdateHistogram(c *C) {
 	defaultBucketCount = 7
 	defer func() { defaultBucketCount = originBucketCount }()
 	c.Assert(UpdateHistogram(q.Hist(), q).ToString(0), Equals,
-		"column:0 ndv:0 totColSize:0\n"+
+		"column:0 ndv:10057 totColSize:0\n"+
 			"num: 10000 lower_bound: 0 upper_bound: 1 repeats: 0\n"+
 			"num: 8 lower_bound: 2 upper_bound: 7 repeats: 0\n"+
 			"num: 11 lower_bound: 8 upper_bound: 19 repeats: 0\n"+

statistics/update.go

@@ -558,10 +558,6 @@ func (h *Handle) handleSingleHistogramUpdate(is infoschema.InfoSchema, rows []ch
 			log.Debugf("decode feedback failed, err: %v", errors.ErrorStack(err))
 		}
 	}
-	// Update the NDV of primary key column.
-	if table.Meta().PKIsHandle && q.tp == pkType {
-		hist.NDV = int64(hist.totalRowCount())
-	}
 	err = h.dumpStatsUpdateToKV(physicalTableID, isIndex, q, hist, cms)
 	return errors.Trace(err)
 }

statistics/update_test.go

@@ -594,7 +594,7 @@ func (s *testStatsUpdateSuite) TestQueryFeedback(c *C) {
 		{
 			// test primary key feedback
 			sql: "select * from t where t.a <= 5",
-			hist: "column:1 ndv:3 totColSize:0\n" +
+			hist: "column:1 ndv:4 totColSize:0\n" +
 				"num: 1 lower_bound: -9223372036854775808 upper_bound: 1 repeats: 0\n" +
 				"num: 1 lower_bound: 2 upper_bound: 2 repeats: 1\n" +
 				"num: 2 lower_bound: 3 upper_bound: 5 repeats: 0",
@@ -1118,3 +1118,72 @@ func (s *testStatsUpdateSuite) TestIndexQueryFeedback(c *C) {
 		c.Assert(tbl.Indices[t.idxID].CMSketch.QueryBytes(val), Equals, t.eqCount)
 	}
 }
+
+func (s *testStatsUpdateSuite) TestFeedbackRanges(c *C) {
+	defer cleanEnv(c, s.store, s.do)
+	testKit := testkit.NewTestKit(c, s.store)
+	h := s.do.StatsHandle()
+	oriProbability := statistics.FeedbackProbability
+	oriNumber := statistics.MaxNumberOfRanges
+	defer func() {
+		statistics.FeedbackProbability = oriProbability
+		statistics.MaxNumberOfRanges = oriNumber
+	}()
+	statistics.FeedbackProbability = 1
+
+	testKit.MustExec("use test")
+	testKit.MustExec("create table t (a tinyint, b tinyint, primary key(a), index idx(a, b))")
+	for i := 0; i < 20; i++ {
+		testKit.MustExec(fmt.Sprintf("insert into t values (%d, %d)", i, i))
+	}
+	h.HandleDDLEvent(<-h.DDLEventCh())
+	c.Assert(h.DumpStatsDeltaToKV(statistics.DumpAll), IsNil)
+	testKit.MustExec("analyze table t with 3 buckets")
+	for i := 30; i < 40; i++ {
+		testKit.MustExec(fmt.Sprintf("insert into t values (%d, %d)", i, i))
+	}
+	c.Assert(h.DumpStatsDeltaToKV(statistics.DumpAll), IsNil)
+	tests := []struct {
+		sql   string
+		hist  string
+		colID int64
+	}{
+		{
+			sql: "select * from t where a <= 50 or (a > 130 and a < 140)",
+			hist: "column:1 ndv:30 totColSize:0\n" +
+				"num: 8 lower_bound: -128 upper_bound: 7 repeats: 0\n" +
+				"num: 8 lower_bound: 8 upper_bound: 15 repeats: 0\n" +
+				"num: 14 lower_bound: 16 upper_bound: 50 repeats: 0",
+			colID: 1,
+		},
+		{
+			sql: "select * from t where a >= 10",
+			hist: "column:1 ndv:30 totColSize:0\n" +
+				"num: 8 lower_bound: -128 upper_bound: 7 repeats: 0\n" +
+				"num: 8 lower_bound: 8 upper_bound: 15 repeats: 0\n" +
+				"num: 14 lower_bound: 16 upper_bound: 127 repeats: 0",
+			colID: 1,
+		},
+		{
+			sql: "select * from t use index(idx) where a = 1 and (b <= 50 or (b > 130 and b < 140))",
+			hist: "column:2 ndv:20 totColSize:20\n" +
+				"num: 7 lower_bound: -128 upper_bound: 6 repeats: 0\n" +
+				"num: 7 lower_bound: 7 upper_bound: 13 repeats: 1\n" +
+				"num: 6 lower_bound: 14 upper_bound: 19 repeats: 1",
+			colID: 2,
+		},
+	}
+	is := s.do.InfoSchema()
+	table, err := is.TableByName(model.NewCIStr("test"), model.NewCIStr("t"))
+	for i, t := range tests {
+		testKit.MustQuery(t.sql)
+		c.Assert(h.DumpStatsDeltaToKV(statistics.DumpAll), IsNil)
+		c.Assert(h.DumpStatsFeedbackToKV(), IsNil)
+		c.Assert(h.HandleUpdateStats(s.do.InfoSchema()), IsNil)
+		c.Assert(err, IsNil)
+		h.Update(is)
+		tblInfo := table.Meta()
+		tbl := h.GetTableStats(tblInfo)
+		c.Assert(tbl.Columns[t.colID].ToString(0), Equals, tests[i].hist)
+	}
+}

types/etc_test.go

@@ -122,7 +122,7 @@ func (s *testTypeEtcSuite) TestMaxFloat(c *C) {
 	}
 
 	for _, t := range tbl {
-		f := getMaxFloat(t.Flen, t.Decimal)
+		f := GetMaxFloat(t.Flen, t.Decimal)
 		c.Assert(f, Equals, t.Expect)
 	}
 }

types/helper.go

@@ -59,7 +59,8 @@ func Truncate(f float64, dec int) float64 {
 	return math.Trunc(tmp) / shift
 }
 
-func getMaxFloat(flen int, decimal int) float64 {
+// GetMaxFloat gets the max float for given flen and decimal.
+func GetMaxFloat(flen int, decimal int) float64 {
 	intPartLen := flen - decimal
 	f := math.Pow10(intPartLen)
 	f -= math.Pow10(-decimal)
@@ -74,7 +75,7 @@ func TruncateFloat(f float64, flen int, decimal int) (float64, error) {
 		return 0, ErrOverflow.GenWithStackByArgs("DOUBLE", "")
 	}
 
-	maxF := getMaxFloat(flen, decimal)
+	maxF := GetMaxFloat(flen, decimal)
 
 	if !math.IsInf(f, 0) {
 		f = Round(f, decimal)