Golang parser.DInt函数代码示例

// golangFillQueryArguments populates the placeholder map with
// types and values from an array of Go values.
// TODO: This does not support arguments of the SQL 'Date' type, as there is not
// an equivalent type in Go's standard library. It's not currently needed by any
// of our internal tables.
func golangFillQueryArguments(pinfo *parser.PlaceholderInfo, args []interface{}) {
	pinfo.Clear()

	for i, arg := range args {
		k := fmt.Sprint(i + 1)
		if arg == nil {
			pinfo.SetValue(k, parser.DNull)
			continue
		}

		// A type switch to handle a few explicit types with special semantics:
		// - Datums are passed along as is.
		// - Time datatypes get special representation in the database.
		var d parser.Datum
		switch t := arg.(type) {
		case parser.Datum:
			d = t
		case time.Time:
			d = parser.MakeDTimestamp(t, time.Microsecond)
		case time.Duration:
			d = &parser.DInterval{Duration: duration.Duration{Nanos: t.Nanoseconds()}}
		case *inf.Dec:
			dd := &parser.DDecimal{}
			dd.Set(t)
			d = dd
		}
		if d == nil {
			// Handle all types which have an underlying type that can be stored in the
			// database.
			// Note: if this reflection becomes a performance concern in the future,
			// commonly used types could be added explicitly into the type switch above
			// for a performance gain.
			val := reflect.ValueOf(arg)
			switch val.Kind() {
			case reflect.Bool:
				d = parser.MakeDBool(parser.DBool(val.Bool()))
			case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
				d = parser.NewDInt(parser.DInt(val.Int()))
			case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
				d = parser.NewDInt(parser.DInt(val.Uint()))
			case reflect.Float32, reflect.Float64:
				d = parser.NewDFloat(parser.DFloat(val.Float()))
			case reflect.String:
				d = parser.NewDString(val.String())
			case reflect.Slice:
				// Handle byte slices.
				if val.Type().Elem().Kind() == reflect.Uint8 {
					d = parser.NewDBytes(parser.DBytes(val.Bytes()))
				}
			}
			if d == nil {
				panic(fmt.Sprintf("unexpected type %T", arg))
			}
		}
		pinfo.SetValue(k, d)
	}
}

// populateExplain invokes explain() with a makeRow method
// which populates a valuesNode.
func (e *explainer) populateExplain(v *valuesNode, plan planNode) error {
	e.makeRow = func(level int, name, field, description string, plan planNode) {
		if e.err != nil {
			return
		}

		row := parser.DTuple{
			parser.NewDInt(parser.DInt(level)),
			parser.NewDString(name),
			parser.NewDString(field),
			parser.NewDString(description),
		}
		if e.showMetadata {
			if plan != nil {
				row = append(row, parser.NewDString(formatColumns(plan.Columns(), e.showTypes)))
				row = append(row, parser.NewDString(plan.Ordering().AsString(plan.Columns())))
			} else {
				row = append(row, emptyString, emptyString)
			}
		}
		if _, err := v.rows.AddRow(row); err != nil {
			e.err = err
		}
	}

	e.err = nil
	e.explain(plan)
	return e.err
}

// DecodeTableValue decodes a value encoded by EncodeTableValue.
func DecodeTableValue(a *DatumAlloc, valType parser.Type, b []byte) (parser.Datum, []byte, error) {
	_, dataOffset, _, typ, err := encoding.DecodeValueTag(b)
	if err != nil {
		return nil, b, err
	}
	if typ == encoding.Null {
		return parser.DNull, b[dataOffset:], nil
	}
	switch valType {
	case parser.TypeBool:
		var x bool
		b, x, err = encoding.DecodeBoolValue(b)
		// No need to chunk allocate DBool as MakeDBool returns either
		// parser.DBoolTrue or parser.DBoolFalse.
		return parser.MakeDBool(parser.DBool(x)), b, err
	case parser.TypeInt:
		var i int64
		b, i, err = encoding.DecodeIntValue(b)
		return a.NewDInt(parser.DInt(i)), b, err
	case parser.TypeFloat:
		var f float64
		b, f, err = encoding.DecodeFloatValue(b)
		return a.NewDFloat(parser.DFloat(f)), b, err
	case parser.TypeDecimal:
		var d *inf.Dec
		b, d, err = encoding.DecodeDecimalValue(b)
		dd := a.NewDDecimal(parser.DDecimal{})
		dd.Set(d)
		return dd, b, err
	case parser.TypeString:
		var data []byte
		b, data, err = encoding.DecodeBytesValue(b)
		return a.NewDString(parser.DString(data)), b, err
	case parser.TypeBytes:
		var data []byte
		b, data, err = encoding.DecodeBytesValue(b)
		return a.NewDBytes(parser.DBytes(data)), b, err
	case parser.TypeDate:
		var i int64
		b, i, err = encoding.DecodeIntValue(b)
		return a.NewDDate(parser.DDate(i)), b, err
	case parser.TypeTimestamp:
		var t time.Time
		b, t, err = encoding.DecodeTimeValue(b)
		return a.NewDTimestamp(parser.DTimestamp{Time: t}), b, err
	case parser.TypeTimestampTZ:
		var t time.Time
		b, t, err = encoding.DecodeTimeValue(b)
		return a.NewDTimestampTZ(parser.DTimestampTZ{Time: t}), b, err
	case parser.TypeInterval:
		var d duration.Duration
		b, d, err = encoding.DecodeDurationValue(b)
		return a.NewDInterval(parser.DInterval{Duration: d}), b, err
	default:
		return nil, nil, errors.Errorf("TODO(pmattis): decoded index value: %s", valType)
	}
}

func benchmarkWriteArray(b *testing.B, format formatCode) {
	a := parser.NewDArray(parser.TypeInt)
	for i := 0; i < 3; i++ {
		if err := a.Append(parser.NewDInt(parser.DInt(1234))); err != nil {
			b.Fatal(err)
		}
	}
	benchmarkWriteType(b, a, format)
}

func (o *ordinalityNode) Next() (bool, error) {
	hasNext, err := o.source.Next()
	if !hasNext || err != nil {
		return hasNext, err
	}
	copy(o.row, o.source.Values())
	// o.row was allocated one spot larger than o.source.Values().
	// Store the ordinality value there.
	o.row[len(o.row)-1] = parser.NewDInt(parser.DInt(o.curCnt))
	o.curCnt++
	return true, nil
}

// colIDArrayToDatum returns an int[] containing the ColumnIDs, or NULL if there
// are no ColumnIDs.
func colIDArrayToDatum(arr []sqlbase.ColumnID) (parser.Datum, error) {
	if len(arr) == 0 {
		return parser.DNull, nil
	}
	d := parser.NewDArray(parser.TypeInt)
	for _, val := range arr {
		if err := d.Append(parser.NewDInt(parser.DInt(val))); err != nil {
			return nil, err
		}
	}
	return d, nil
}

func TestRowContainer(t *testing.T) {
	defer leaktest.AfterTest(t)()

	for _, numCols := range []int{1, 2, 3, 5, 10, 15} {
		for _, numRows := range []int{5, 10, 100} {
			for _, numPops := range []int{0, 1, 2, numRows / 3, numRows / 2} {
				resCol := make(ResultColumns, numCols)
				for i := range resCol {
					resCol[i] = ResultColumn{Typ: parser.TypeInt}
				}
				m := mon.MakeUnlimitedMonitor(context.Background(), "test", nil, nil, math.MaxInt64)
				rc := NewRowContainer(m.MakeBoundAccount(context.Background()), resCol, 0)
				row := make(parser.DTuple, numCols)
				for i := 0; i < numRows; i++ {
					for j := range row {
						row[j] = parser.NewDInt(parser.DInt(i*numCols + j))
					}
					if err := rc.AddRow(row); err != nil {
						t.Fatal(err)
					}
				}

				for i := 0; i < numPops; i++ {
					rc.PopFirst()
				}

				// Given that we just deleted numPops rows, we have numRows -
				// numPops rows remaining.
				if rc.Len() != numRows-numPops {
					t.Fatalf("invalid length, expected %d got %d", numRows-numPops, rc.Len())
				}

				// what was previously rc.At(i + numPops) is now rc.At(i).
				for i := 0; i < rc.Len(); i++ {
					row := rc.At(i)
					for j := range row {
						dint, ok := row[j].(*parser.DInt)
						if !ok || int(*dint) != (i+numPops)*numCols+j {
							t.Fatalf("invalid value %+v on row %d, col %d", row[j], i+numPops, j)
						}
					}
				}
			}
		}
	}
}

// RandDatum generates a random Datum of the given type.
// If null is true, the datum can be DNull.
func RandDatum(rng *rand.Rand, typ ColumnType_Kind, null bool) parser.Datum {
	if null && rng.Intn(10) == 0 {
		return parser.DNull
	}
	switch typ {
	case ColumnType_BOOL:
		return parser.MakeDBool(rng.Intn(2) == 1)
	case ColumnType_INT:
		return parser.NewDInt(parser.DInt(rng.Int63()))
	case ColumnType_FLOAT:
		return parser.NewDFloat(parser.DFloat(rng.NormFloat64()))
	case ColumnType_DECIMAL:
		d := &parser.DDecimal{}
		d.Dec.SetScale(inf.Scale(rng.Intn(40) - 20))
		d.Dec.SetUnscaled(rng.Int63())
		return d
	case ColumnType_DATE:
		return parser.NewDDate(parser.DDate(rng.Intn(10000)))
	case ColumnType_TIMESTAMP:
		return &parser.DTimestamp{Time: time.Unix(rng.Int63n(1000000), rng.Int63n(1000000))}
	case ColumnType_INTERVAL:
		return &parser.DInterval{Duration: duration.Duration{Months: rng.Int63n(1000),
			Days:  rng.Int63n(1000),
			Nanos: rng.Int63n(1000000),
		}}
	case ColumnType_STRING:
		// Generate a random ASCII string.
		p := make([]byte, rng.Intn(10))
		for i := range p {
			p[i] = byte(1 + rng.Intn(127))
		}
		return parser.NewDString(string(p))
	case ColumnType_BYTES:
		p := make([]byte, rng.Intn(10))
		_, _ = rng.Read(p)
		return parser.NewDBytes(parser.DBytes(p))
	case ColumnType_TIMESTAMPTZ:
		return &parser.DTimestampTZ{Time: time.Unix(rng.Int63n(1000000), rng.Int63n(1000000))}
	case ColumnType_INT_ARRAY:
		// TODO(cuongdo): we don't support for persistence of arrays yet
		return parser.DNull
	default:
		panic(fmt.Sprintf("invalid type %s", typ))
	}
}

// MakePrimaryIndexKey creates a key prefix that corresponds to a table row
// (in the primary index); it is intended for tests.
//
// The value types must match the primary key columns (or a prefix of them);
// supported types are: - Datum
//  - bool (converts to DBool)
//  - int (converts to DInt)
//  - string (converts to DString)
func MakePrimaryIndexKey(desc *TableDescriptor, vals ...interface{}) (roachpb.Key, error) {
	index := &desc.PrimaryIndex
	if len(vals) > len(index.ColumnIDs) {
		return nil, errors.Errorf("got %d values, PK has %d columns", len(vals), len(index.ColumnIDs))
	}
	datums := make([]parser.Datum, len(vals))
	for i, v := range vals {
		switch v := v.(type) {
		case bool:
			datums[i] = parser.MakeDBool(parser.DBool(v))
		case int:
			datums[i] = parser.NewDInt(parser.DInt(v))
		case string:
			datums[i] = parser.NewDString(v)
		case parser.Datum:
			datums[i] = v
		default:
			return nil, errors.Errorf("unexpected value type %T", v)
		}
		// Check that the value type matches.
		colID := index.ColumnIDs[i]
		for _, c := range desc.Columns {
			if c.ID == colID {
				if t := DatumTypeToColumnKind(datums[i].ResolvedType()); t != c.Type.Kind {
					return nil, errors.Errorf("column %d of type %s, got value of type %s", i, c.Type.Kind, t)
				}
				break
			}
		}
	}
	// Create the ColumnID to index in datums slice map needed by
	// MakeIndexKeyPrefix.
	colIDToRowIndex := make(map[ColumnID]int)
	for i := range vals {
		colIDToRowIndex[index.ColumnIDs[i]] = i
	}

	keyPrefix := MakeIndexKeyPrefix(desc, index.ID)
	key, _, err := EncodeIndexKey(desc, index, colIDToRowIndex, datums, keyPrefix)
	if err != nil {
		return nil, err
	}
	return roachpb.Key(key), nil
}

func TestUnorderedSync(t *testing.T) {
	defer leaktest.AfterTest(t)()

	columnTypeInt := &sqlbase.ColumnType{Kind: sqlbase.ColumnType_INT}
	mrc := &MultiplexedRowChannel{}
	mrc.Init(5)
	for i := 1; i <= 5; i++ {
		go func(i int) {
			for j := 1; j <= 100; j++ {
				a := sqlbase.DatumToEncDatum(*columnTypeInt, parser.NewDInt(parser.DInt(i)))
				b := sqlbase.DatumToEncDatum(*columnTypeInt, parser.NewDInt(parser.DInt(j)))
				row := sqlbase.EncDatumRow{a, b}
				mrc.PushRow(row)
			}
			mrc.Close(nil)
		}(i)
	}
	var retRows sqlbase.EncDatumRows
	for {
		row, err := mrc.NextRow()
		if err != nil {
			t.Fatal(err)
		}
		if row == nil {
			break
		}
		retRows = append(retRows, row)
	}
	// Verify all elements.
	for i := 1; i <= 5; i++ {
		j := 1
		for _, row := range retRows {
			if int(*(row[0].Datum.(*parser.DInt))) == i {
				if int(*(row[1].Datum.(*parser.DInt))) != j {
					t.Errorf("Expected [%d %d], got %s", i, j, row)
				}
				j++
			}
		}
		if j != 101 {
			t.Errorf("Missing [%d %d]", i, j)
		}
	}

	// Test case when one source closes with an error.
	mrc = &MultiplexedRowChannel{}
	mrc.Init(5)
	for i := 1; i <= 5; i++ {
		go func(i int) {
			for j := 1; j <= 100; j++ {
				a := sqlbase.DatumToEncDatum(*columnTypeInt, parser.NewDInt(parser.DInt(i)))
				b := sqlbase.DatumToEncDatum(*columnTypeInt, parser.NewDInt(parser.DInt(j)))
				row := sqlbase.EncDatumRow{a, b}
				mrc.PushRow(row)
			}
			var err error
			if i == 3 {
				err = fmt.Errorf("Test error")
			}
			mrc.Close(err)
		}(i)
	}
	for {
		row, err := mrc.NextRow()
		if err != nil {
			if err.Error() != "Test error" {
				t.Error(err)
			}
			break
		}
		if row == nil {
			t.Error("Did not receive expected error")
		}
	}
}

// TestAdminAPIZoneDetails verifies the zone configuration information returned
// for both DatabaseDetailsResponse AND TableDetailsResponse.
func TestAdminAPIZoneDetails(t *testing.T) {
	defer leaktest.AfterTest(t)()
	s, _, _ := serverutils.StartServer(t, base.TestServerArgs{})
	defer s.Stopper().Stop()
	ts := s.(*TestServer)

	// Create database and table.
	ac := log.AmbientContext{Tracer: tracing.NewTracer()}
	ctx, span := ac.AnnotateCtxWithSpan(context.Background(), "test")
	defer span.Finish()
	session := sql.NewSession(
		ctx, sql.SessionArgs{User: security.RootUser}, ts.sqlExecutor, nil, &sql.MemoryMetrics{})
	session.StartUnlimitedMonitor()
	setupQueries := []string{
		"CREATE DATABASE test",
		"CREATE TABLE test.tbl (val STRING)",
	}
	for _, q := range setupQueries {
		res := ts.sqlExecutor.ExecuteStatements(session, q, nil)
		defer res.Close()
		if res.ResultList[0].Err != nil {
			t.Fatalf("error executing '%s': %s", q, res.ResultList[0].Err)
		}
	}

	// Function to verify the zone for table "test.tbl" as returned by the Admin
	// API.
	verifyTblZone := func(
		expectedZone config.ZoneConfig, expectedLevel serverpb.ZoneConfigurationLevel,
	) {
		var resp serverpb.TableDetailsResponse
		if err := getAdminJSONProto(s, "databases/test/tables/tbl", &resp); err != nil {
			t.Fatal(err)
		}
		if a, e := &resp.ZoneConfig, &expectedZone; !proto.Equal(a, e) {
			t.Errorf("actual table zone config %v did not match expected value %v", a, e)
		}
		if a, e := resp.ZoneConfigLevel, expectedLevel; a != e {
			t.Errorf("actual table ZoneConfigurationLevel %s did not match expected value %s", a, e)
		}
		if t.Failed() {
			t.FailNow()
		}
	}

	// Function to verify the zone for database "test" as returned by the Admin
	// API.
	verifyDbZone := func(
		expectedZone config.ZoneConfig, expectedLevel serverpb.ZoneConfigurationLevel,
	) {
		var resp serverpb.DatabaseDetailsResponse
		if err := getAdminJSONProto(s, "databases/test", &resp); err != nil {
			t.Fatal(err)
		}
		if a, e := &resp.ZoneConfig, &expectedZone; !proto.Equal(a, e) {
			t.Errorf("actual db zone config %v did not match expected value %v", a, e)
		}
		if a, e := resp.ZoneConfigLevel, expectedLevel; a != e {
			t.Errorf("actual db ZoneConfigurationLevel %s did not match expected value %s", a, e)
		}
		if t.Failed() {
			t.FailNow()
		}
	}

	// Function to store a zone config for a given object ID.
	setZone := func(zoneCfg config.ZoneConfig, id sqlbase.ID) {
		zoneBytes, err := zoneCfg.Marshal()
		if err != nil {
			t.Fatal(err)
		}
		const query = `INSERT INTO system.zones VALUES($1, $2)`
		params := parser.NewPlaceholderInfo()
		params.SetValue(`1`, parser.NewDInt(parser.DInt(id)))
		params.SetValue(`2`, parser.NewDBytes(parser.DBytes(zoneBytes)))
		res := ts.sqlExecutor.ExecuteStatements(session, query, params)
		defer res.Close()
		if res.ResultList[0].Err != nil {
			t.Fatalf("error executing '%s': %s", query, res.ResultList[0].Err)
		}
	}

	// Verify zone matches cluster default.
	verifyDbZone(config.DefaultZoneConfig(), serverpb.ZoneConfigurationLevel_CLUSTER)
	verifyTblZone(config.DefaultZoneConfig(), serverpb.ZoneConfigurationLevel_CLUSTER)

	// Get ID path for table. This will be an array of three IDs, containing the ID of the root namespace,
	// the database, and the table (in that order).
	idPath, err := ts.admin.queryDescriptorIDPath(session, []string{"test", "tbl"})
	if err != nil {
		t.Fatal(err)
	}

	// Apply zone configuration to database and check again.
	dbZone := config.ZoneConfig{
		RangeMinBytes: 456,
	}
	setZone(dbZone, idPath[1])
//.........这里部分代码省略.........

func TestOrderedSync(t *testing.T) {
	defer leaktest.AfterTest(t)()

	columnTypeInt := &sqlbase.ColumnType{Kind: sqlbase.ColumnType_INT}
	v := [6]sqlbase.EncDatum{}
	for i := range v {
		v[i] = sqlbase.DatumToEncDatum(*columnTypeInt, parser.NewDInt(parser.DInt(i)))
	}

	asc := encoding.Ascending
	desc := encoding.Descending

	testCases := []struct {
		sources  []sqlbase.EncDatumRows
		ordering sqlbase.ColumnOrdering
		expected sqlbase.EncDatumRows
	}{
		{
			sources: []sqlbase.EncDatumRows{
				{
					{v[0], v[1], v[4]},
					{v[0], v[1], v[2]},
					{v[0], v[2], v[3]},
					{v[1], v[1], v[3]},
				},
				{
					{v[1], v[0], v[4]},
				},
				{
					{v[0], v[0], v[0]},
					{v[4], v[4], v[4]},
				},
			},
			ordering: sqlbase.ColumnOrdering{
				{ColIdx: 0, Direction: asc},
				{ColIdx: 1, Direction: asc},
			},
			expected: sqlbase.EncDatumRows{
				{v[0], v[0], v[0]},
				{v[0], v[1], v[4]},
				{v[0], v[1], v[2]},
				{v[0], v[2], v[3]},
				{v[1], v[0], v[4]},
				{v[1], v[1], v[3]},
				{v[4], v[4], v[4]},
			},
		},
		{
			sources: []sqlbase.EncDatumRows{
				{},
				{
					{v[1], v[0], v[4]},
				},
				{
					{v[3], v[4], v[1]},
					{v[4], v[4], v[4]},
					{v[3], v[2], v[0]},
				},
				{
					{v[4], v[4], v[5]},
					{v[3], v[3], v[0]},
					{v[0], v[0], v[0]},
				},
			},
			ordering: sqlbase.ColumnOrdering{
				{ColIdx: 1, Direction: desc},
				{ColIdx: 0, Direction: asc},
				{ColIdx: 2, Direction: asc},
			},
			expected: sqlbase.EncDatumRows{
				{v[3], v[4], v[1]},
				{v[4], v[4], v[4]},
				{v[4], v[4], v[5]},
				{v[3], v[3], v[0]},
				{v[3], v[2], v[0]},
				{v[0], v[0], v[0]},
				{v[1], v[0], v[4]},
			},
		},
	}
	for testIdx, c := range testCases {
		var sources []RowSource
		for _, srcRows := range c.sources {
			rowBuf := &RowBuffer{rows: srcRows}
			sources = append(sources, rowBuf)
		}
		src, err := makeOrderedSync(c.ordering, sources)
		if err != nil {
			t.Fatal(err)
		}
		var retRows sqlbase.EncDatumRows
		for {
			row, err := src.NextRow()
			if err != nil {
				t.Fatal(err)
			}
			if row == nil {
				break
			}
			retRows = append(retRows, row)
//.........这里部分代码省略.........

func TestMergeJoiner(t *testing.T) {
	defer leaktest.AfterTest(t)()
	v := [6]sqlbase.EncDatum{}
	for i := range v {
		v[i] = sqlbase.DatumToEncDatum(sqlbase.ColumnType_INT, parser.NewDInt(parser.DInt(i)))
	}
	null := sqlbase.EncDatum{Datum: parser.DNull}

	testCases := []struct {
		spec     MergeJoinerSpec
		inputs   []sqlbase.EncDatumRows
		expected sqlbase.EncDatumRows
	}{
		{
			spec: MergeJoinerSpec{
				LeftOrdering: convertToSpecOrdering(
					sqlbase.ColumnOrdering{
						{ColIdx: 0, Direction: encoding.Ascending},
					}),
				LeftTypes: []sqlbase.ColumnType_Kind{
					sqlbase.ColumnType_INT,
					sqlbase.ColumnType_INT,
				},
				RightOrdering: convertToSpecOrdering(
					sqlbase.ColumnOrdering{
						{ColIdx: 0, Direction: encoding.Ascending},
					}),
				RightTypes: []sqlbase.ColumnType_Kind{
					sqlbase.ColumnType_INT,
					sqlbase.ColumnType_INT,
					sqlbase.ColumnType_INT,
				},
				Type:          JoinType_INNER,
				OutputColumns: []uint32{0, 3, 4},
				// Implicit @1 = @3 constraint.
			},
			inputs: []sqlbase.EncDatumRows{
				{
					{v[0], v[0]},
					{v[1], v[4]},
					{v[2], v[4]},
					{v[3], v[1]},
					{v[4], v[5]},
					{v[5], v[5]},
				},
				{
					{v[1], v[0], v[4]},
					{v[3], v[4], v[1]},
					{v[4], v[4], v[5]},
				},
			},
			expected: sqlbase.EncDatumRows{
				{v[1], v[0], v[4]},
				{v[3], v[4], v[1]},
				{v[4], v[4], v[5]},
			},
		},
		{
			spec: MergeJoinerSpec{
				LeftOrdering: convertToSpecOrdering(
					sqlbase.ColumnOrdering{
						{ColIdx: 0, Direction: encoding.Ascending},
					}),
				LeftTypes: []sqlbase.ColumnType_Kind{
					sqlbase.ColumnType_INT,
					sqlbase.ColumnType_INT,
				},
				RightOrdering: convertToSpecOrdering(
					sqlbase.ColumnOrdering{
						{ColIdx: 0, Direction: encoding.Ascending},
					}),
				RightTypes: []sqlbase.ColumnType_Kind{
					sqlbase.ColumnType_INT,
					sqlbase.ColumnType_INT,
					sqlbase.ColumnType_INT,
				},
				Type:          JoinType_INNER,
				OutputColumns: []uint32{0, 1, 3},
				// Implicit @1 = @3 constraint.
			},
			inputs: []sqlbase.EncDatumRows{
				{
					{v[0], v[0]},
					{v[0], v[1]},
				},
				{
					{v[0], v[4]},
					{v[0], v[1]},
					{v[0], v[0]},
					{v[0], v[5]},
					{v[0], v[4]},
				},
			},
			expected: sqlbase.EncDatumRows{
				{v[0], v[0], v[4]},
				{v[0], v[0], v[1]},
				{v[0], v[0], v[0]},
				{v[0], v[0], v[5]},
				{v[0], v[0], v[4]},
				{v[0], v[1], v[4]},
//.........这里部分代码省略.........

func TestSorter(t *testing.T) {
	defer leaktest.AfterTest(t)()
	v := [6]sqlbase.EncDatum{}
	for i := range v {
		v[i].SetDatum(sqlbase.ColumnType_INT, parser.NewDInt(parser.DInt(i)))
	}

	asc := encoding.Ascending
	desc := encoding.Descending

	testCases := []struct {
		spec     SorterSpec
		input    sqlbase.EncDatumRows
		expected sqlbase.EncDatumRows
	}{
		{
			// No specified input ordering and unspecified limit.
			spec: SorterSpec{
				OutputOrdering: convertToSpecOrdering(
					sqlbase.ColumnOrdering{
						{ColIdx: 0, Direction: asc},
						{ColIdx: 1, Direction: desc},
						{ColIdx: 2, Direction: asc},
					}),
			},
			input: sqlbase.EncDatumRows{
				{v[1], v[0], v[4]},
				{v[3], v[4], v[1]},
				{v[4], v[4], v[4]},
				{v[3], v[2], v[0]},
				{v[4], v[4], v[5]},
				{v[3], v[3], v[0]},
				{v[0], v[0], v[0]},
			},
			expected: sqlbase.EncDatumRows{
				{v[0], v[0], v[0]},
				{v[1], v[0], v[4]},
				{v[3], v[4], v[1]},
				{v[3], v[3], v[0]},
				{v[3], v[2], v[0]},
				{v[4], v[4], v[4]},
				{v[4], v[4], v[5]},
			},
		}, {
			// No specified input ordering but specified limit.
			spec: SorterSpec{
				Limit: 4,
				OutputOrdering: convertToSpecOrdering(
					sqlbase.ColumnOrdering{
						{ColIdx: 0, Direction: asc},
						{ColIdx: 1, Direction: asc},
						{ColIdx: 2, Direction: asc},
					}),
			},
			input: sqlbase.EncDatumRows{
				{v[3], v[3], v[0]},
				{v[3], v[4], v[1]},
				{v[1], v[0], v[4]},
				{v[0], v[0], v[0]},
				{v[4], v[4], v[4]},
				{v[4], v[4], v[5]},
				{v[3], v[2], v[0]},
			},
			expected: sqlbase.EncDatumRows{
				{v[0], v[0], v[0]},
				{v[1], v[0], v[4]},
				{v[3], v[2], v[0]},
				{v[3], v[3], v[0]},
			},
		}, {
			// Specified match ordering length but no specified limit.
			spec: SorterSpec{
				OrderingMatchLen: 2,
				OutputOrdering: convertToSpecOrdering(
					sqlbase.ColumnOrdering{
						{ColIdx: 0, Direction: asc},
						{ColIdx: 1, Direction: asc},
						{ColIdx: 2, Direction: asc},
					}),
			},
			input: sqlbase.EncDatumRows{
				{v[0], v[1], v[2]},
				{v[0], v[1], v[0]},
				{v[1], v[0], v[5]},
				{v[1], v[1], v[5]},
				{v[1], v[1], v[4]},
				{v[3], v[4], v[3]},
				{v[3], v[4], v[2]},
				{v[3], v[5], v[1]},
				{v[4], v[4], v[5]},
				{v[4], v[4], v[4]},
			},
			expected: sqlbase.EncDatumRows{
				{v[0], v[1], v[0]},
				{v[0], v[1], v[2]},
				{v[1], v[0], v[5]},
				{v[1], v[1], v[4]},
				{v[1], v[1], v[5]},
				{v[3], v[4], v[2]},
				{v[3], v[4], v[3]},
//.........这里部分代码省略.........

// RowModuloFn creates a GenValueFn that returns the row number modulo a given
// value as a DInt
func RowModuloFn(modulo int) GenValueFn {
	return func(row int) parser.Datum {
		return parser.NewDInt(parser.DInt(row % modulo))
	}
}