Golang types.Compare函数代码示例

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本文整理汇总了Golang中github.com/pingcap/tidb/util/types.Compare函数的典型用法代码示例。如果您正苦于以下问题：Golang Compare函数的具体用法？Golang Compare怎么用？Golang Compare使用的例子？那么恭喜您, 这里精选的函数代码示例或许可以为您提供帮助。

在下文中一共展示了Compare函数的20个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于我们的系统推荐出更棒的Golang代码示例。

示例1: handleComparisonOp

func (e *Evaluator) handleComparisonOp(o *ast.BinaryOperationExpr) bool {
	a, b := types.Coerce(o.L.GetValue(), o.R.GetValue())
	if types.IsNil(a) || types.IsNil(b) {
		// for <=>, if a and b are both nil, return true.
		// if a or b is nil, return false.
		if o.Op == opcode.NullEQ {
			if types.IsNil(a) || types.IsNil(b) {
				o.SetValue(oneI64)
			} else {
				o.SetValue(zeroI64)
			}
		} else {
			o.SetValue(nil)
		}
		return true
	}

	n, err := types.Compare(a, b)
	if err != nil {
		e.err = errors.Trace(err)
		return false
	}

	r, err := getCompResult(o.Op, n)
	if err != nil {
		e.err = errors.Trace(err)
		return false
	}
	if r {
		o.SetValue(oneI64)
	} else {
		o.SetValue(zeroI64)
	}
	return true
}

开发者ID:lovedboy，项目名称:tidb，代码行数:35，代码来源:evaluator_binop.go

示例2: Less

// Less implements sort.Interface Less interface.
func (t *orderByTable) Less(i, j int) bool {
	for index, asc := range t.Ascs {
		v1 := t.Rows[i].Key[index]
		v2 := t.Rows[j].Key[index]

		ret, err := types.Compare(v1, v2)
		if err != nil {
			// we just have to log this error and skip it.
			// TODO: record this error and handle it out later.
			log.Errorf("compare %v %v err %v", v1, v2, err)
		}

		if !asc {
			ret = -ret
		}

		if ret < 0 {
			return true
		} else if ret > 0 {
			return false
		}
	}

	return false
}

开发者ID:no2key，项目名称:tidb，代码行数:26，代码来源:orderby.go

示例3: replaceRow

func replaceRow(ctx context.Context, t table.Table, handle int64, replaceRow []interface{}) error {
	row, err := t.Row(ctx, handle)
	if err != nil {
		return errors.Trace(err)
	}

	result := 0
	isReplace := false
	touched := make(map[int]bool, len(row))
	for i, val := range row {
		result, err = types.Compare(val, replaceRow[i])
		if err != nil {
			return errors.Trace(err)
		}
		if result != 0 {
			touched[i] = true
			isReplace = true
		}
	}

	if isReplace {
		variable.GetSessionVars(ctx).AddAffectedRows(1)
		if err = t.UpdateRecord(ctx, handle, row, replaceRow, touched); err != nil {
			return errors.Trace(err)
		}
	}

	return nil
}

开发者ID:yzl11，项目名称:vessel，代码行数:29，代码来源:replace.go

示例4: caseExpr

func (e *Evaluator) caseExpr(v *ast.CaseExpr) bool {
	var target interface{} = true
	if v.Value != nil {
		target = v.Value.GetValue()
	}
	if target != nil {
		for _, val := range v.WhenClauses {
			cmp, err := types.Compare(target, val.Expr.GetValue())
			if err != nil {
				e.err = errors.Trace(err)
				return false
			}
			if cmp == 0 {
				v.SetValue(val.Result.GetValue())
				return true
			}
		}
	}
	if v.ElseClause != nil {
		v.SetValue(v.ElseClause.GetValue())
	} else {
		v.SetValue(nil)
	}
	return true
}

开发者ID:mrtoms，项目名称:tidb，代码行数:25，代码来源:evaluator.go

示例5: checkAnyResult

func (e *Evaluator) checkAnyResult(cs *ast.CompareSubqueryExpr, lv interface{}, result []interface{}) (interface{}, error) {
	hasNull := false
	for _, v := range result {
		if v == nil {
			hasNull = true
			continue
		}

		comRes, err := types.Compare(lv, v)
		if err != nil {
			return nil, errors.Trace(err)
		}

		res, err := getCompResult(cs.Op, comRes)
		if err != nil {
			return nil, errors.Trace(err)
		}
		if res {
			return true, nil
		}
	}

	if hasNull {
		// If no matched but we get null, return null.
		// Like `insert t (c) values (1),(2),(null)`, then
		// `select 0 > any (select c from t)`, returns null.
		return nil, nil
	}

	return false, nil
}

开发者ID:xudongQiu，项目名称:tidb，代码行数:31，代码来源:evaluator.go

示例6: checkInList

func (e *Evaluator) checkInList(not bool, in interface{}, list []interface{}) (interface{}, error) {
	hasNull := false
	for _, v := range list {
		if types.IsNil(v) {
			hasNull = true
			continue
		}

		r, err := types.Compare(in, v)
		if err != nil {
			return nil, errors.Trace(err)
		}

		if r == 0 {
			return !not, nil
		}
	}

	if hasNull {
		// if no matched but we got null in In, return null
		// e.g 1 in (null, 2, 3) returns null
		return nil, nil
	}

	return not, nil
}

开发者ID:mrtoms，项目名称:tidb，代码行数:26，代码来源:evaluator.go

示例7: indexCompare

// comparison function that takes minNotNullVal and maxVal into account.
func indexCompare(a interface{}, b interface{}) int {
	if a == nil && b == nil {
		return 0
	} else if b == nil {
		return 1
	} else if b == nil {
		return -1
	}
	// a and b both not nil
	if a == minNotNullVal && b == minNotNullVal {
		return 0
	} else if b == minNotNullVal {
		return 1
	} else if a == minNotNullVal {
		return -1
	}

	// a and b both not min value
	if a == maxVal && b == maxVal {
		return 0
	} else if a == maxVal {
		return 1
	} else if b == maxVal {
		return -1
	}

	n, err := types.Compare(a, b)
	if err != nil {
		// Old compare panics if err, so here we do the same thing now.
		// TODO: return err instead of panic.
		panic(fmt.Sprintf("should never happend %v", err))
	}
	return n
}

开发者ID:kevinhuo88888，项目名称:tidb，代码行数:35，代码来源:index.go

示例8: evalComparisonOp

// operator: >=, >, <=, <, !=, <>, = <=>, etc.
// see https://dev.mysql.com/doc/refman/5.7/en/comparison-operators.html
func (o *BinaryOperation) evalComparisonOp(ctx context.Context, args map[interface{}]interface{}) (interface{}, error) {
	//TODO: support <=> later
	a, b, err := o.get2(ctx, args)
	if err != nil {
		return nil, err
	}

	if a == nil || b == nil {
		// TODO: for <=>, if a and b are both nil, return true
		return nil, nil
	}

	n, err := types.Compare(a, b)
	if err != nil {
		return nil, o.traceErr(err)
	}

	switch o.Op {
	case opcode.LT:
		return n < 0, nil
	case opcode.LE:
		return n <= 0, nil
	case opcode.GE:
		return n >= 0, nil
	case opcode.GT:
		return n > 0, nil
	case opcode.EQ:
		return n == 0, nil
	case opcode.NE:
		return n != 0, nil
	default:
		return nil, o.errorf("invalid op %v in comparision operation", o.Op)
	}
}

开发者ID:eeertekin，项目名称:tidb，代码行数:36，代码来源:binop.go

示例9: checkInList

func (n *PatternIn) checkInList(in interface{}, list []interface{}) (interface{}, error) {
	hasNull := false
	for _, v := range list {
		if types.IsNil(v) {
			hasNull = true
			continue
		}

		r, err := types.Compare(in, v)
		if err != nil {
			return nil, err
		}

		if r == 0 {
			return !n.Not, nil
		}
	}

	if hasNull {
		// if no matched but we got null in In, return null
		// e.g 1 in (null, 2, 3) returns null
		return nil, nil
	}

	return n.Not, nil
}

开发者ID:fuxiaohei，项目名称:tidb，代码行数:26，代码来源:in.go

示例10: evalComparisonOp

// operator: >=, >, <=, <, !=, <>, = <=>, etc.
// see https://dev.mysql.com/doc/refman/5.7/en/comparison-operators.html
func (o *BinaryOperation) evalComparisonOp(ctx context.Context, args map[interface{}]interface{}) (interface{}, error) {
	//TODO: support <=> later
	a, b, err := o.get2(ctx, args)
	if err != nil {
		return nil, err
	}

	if a == nil || b == nil {
		// for <=>, if a and b are both nil, return true.
		// if a or b is nil, return false.
		if o.Op == opcode.NullEQ {
			return a == b, nil
		}

		return nil, nil
	}

	n, err := types.Compare(a, b)
	if err != nil {
		return nil, o.traceErr(err)
	}

	r, err := getCompResult(o.Op, n)
	if err != nil {
		return nil, o.errorf(err.Error())
	}

	return r, nil
}

开发者ID:nengwang，项目名称:tidb，代码行数:31，代码来源:binop.go

示例11: updateMaxMin

func (n *AggregateFuncExpr) updateMaxMin(max bool) error {
	ctx := n.GetContext()
	if len(n.Args) != 1 {
		return errors.New("Wrong number of args for AggFuncFirstRow")
	}
	v := n.Args[0].GetValue()
	if !ctx.evaluated {
		ctx.Value = v
		ctx.evaluated = true
		return nil
	}
	c, err := types.Compare(ctx.Value, v)
	if err != nil {
		return errors.Trace(err)
	}
	if max {
		if c == -1 {
			ctx.Value = v
		}
	} else {
		if c == 1 {
			ctx.Value = v
		}

	}
	return nil
}

开发者ID:astaxie，项目名称:tidb，代码行数:27，代码来源:functions.go

示例12: patternIn

func (e *Evaluator) patternIn(n *ast.PatternInExpr) bool {
	lhs := n.Expr.GetValue()
	if types.IsNil(lhs) {
		n.SetValue(nil)
		return true
	}
	hasNull := false
	for _, v := range n.List {
		if types.IsNil(v.GetValue()) {
			hasNull = true
			continue
		}
		r, err := types.Compare(n.Expr.GetValue(), v.GetValue())
		if err != nil {
			e.err = errors.Trace(err)
			return false
		}
		if r == 0 {
			n.SetValue(boolToInt64(!n.Not))
			return true
		}
	}
	if hasNull {
		// if no matched but we got null in In, return null
		// e.g 1 in (null, 2, 3) returns null
		n.SetValue(nil)
		return true
	}
	n.SetValue(boolToInt64(n.Not))
	return true
}

开发者ID:mrtoms，项目名称:tidb，代码行数:31，代码来源:evaluator.go

示例13: indexCompare

// comparison function that takes minNotNullVal and maxVal into account.
func indexCompare(a interface{}, b interface{}) int {
	if a == nil && b == nil {
		return 0
	} else if b == nil {
		return 1
	} else if b == nil {
		return -1
	}
	// a and b both not nil
	if a == minNotNullVal && b == minNotNullVal {
		return 0
	} else if b == minNotNullVal {
		return 1
	} else if a == minNotNullVal {
		return -1
	}

	// a and b both not min value
	if a == maxVal && b == maxVal {
		return 0
	} else if a == maxVal {
		return 1
	} else if b == maxVal {
		return -1
	}

	return types.Compare(a, b)
}

开发者ID:npk，项目名称:tidb，代码行数:29，代码来源:index.go

示例14: indexColumnCompare

// comparison function that takes minNotNullVal and maxVal into account.
func indexColumnCompare(a interface{}, b interface{}) (int, error) {
	if a == nil && b == nil {
		return 0, nil
	} else if b == nil {
		return 1, nil
	} else if a == nil {
		return -1, nil
	}

	// a and b both not nil
	if a == plan.MinNotNullVal && b == plan.MinNotNullVal {
		return 0, nil
	} else if b == plan.MinNotNullVal {
		return 1, nil
	} else if a == plan.MinNotNullVal {
		return -1, nil
	}

	// a and b both not min value
	if a == plan.MaxVal && b == plan.MaxVal {
		return 0, nil
	} else if a == plan.MaxVal {
		return 1, nil
	} else if b == plan.MaxVal {
		return -1, nil
	}

	n, err := types.Compare(a, b)
	if err != nil {
		return 0, errors.Trace(err)
	}
	return n, nil
}

开发者ID:lovedboy，项目名称:tidb，代码行数:34，代码来源:executor.go

示例15: Update

// Update implements AggregationFunction interface.
func (mmf *maxMinFunction) Update(row []types.Datum, groupKey []byte, ectx context.Context) error {
	ctx := mmf.getContext(groupKey)
	if len(mmf.Args) != 1 {
		return errors.New("Wrong number of args for AggFuncMaxMin")
	}
	a := mmf.Args[0]
	value, err := a.Eval(row, ectx)
	if err != nil {
		return errors.Trace(err)
	}
	if !ctx.Evaluated {
		ctx.Value = value.GetValue()
	}
	if value.GetValue() == nil {
		return nil
	}
	var c int
	c, err = types.Compare(ctx.Value, value.GetValue())
	if err != nil {
		return errors.Trace(err)
	}
	if (mmf.isMax && c == -1) || (!mmf.isMax && c == 1) {
		ctx.Value = value.GetValue()
	}
	ctx.Evaluated = true
	return nil
}

开发者ID:duzhanyuan，项目名称:tidb，代码行数:28，代码来源:aggregation.go

示例16: buildTableRanges

func (r *rangeBuilder) buildTableRanges(rangePoints []rangePoint) []TableRange {
	tableRanges := make([]TableRange, 0, len(rangePoints)/2)
	for i := 0; i < len(rangePoints); i += 2 {
		startPoint := rangePoints[i]
		if startPoint.value == nil || startPoint.value == MinNotNullVal {
			startPoint.value = math.MinInt64
		}
		startInt, err := types.ToInt64(startPoint.value)
		if err != nil {
			r.err = errors.Trace(err)
			return tableRanges
		}
		cmp, err := types.Compare(startInt, startPoint.value)
		if err != nil {
			r.err = errors.Trace(err)
			return tableRanges
		}
		if cmp < 0 || (cmp == 0 && startPoint.excl) {
			startInt++
		}
		endPoint := rangePoints[i+1]
		if endPoint.value == nil {
			endPoint.value = math.MinInt64
		} else if endPoint.value == MaxVal {
			endPoint.value = math.MaxInt64
		}
		endInt, err := types.ToInt64(endPoint.value)
		if err != nil {
			r.err = errors.Trace(err)
			return tableRanges
		}
		cmp, err = types.Compare(endInt, endPoint.value)
		if err != nil {
			r.err = errors.Trace(err)
			return tableRanges
		}
		if cmp > 0 || (cmp == 0 && endPoint.excl) {
			endInt--
		}
		if startInt > endInt {
			continue
		}
		tableRanges = append(tableRanges, TableRange{LowVal: startInt, HighVal: endInt})
	}
	return tableRanges
}

开发者ID:52Jolynn，项目名称:tidb，代码行数:46，代码来源:range.go

示例17: isPointLookup

func (r *indexPlan) isPointLookup(span *indexSpan) bool {
	equalOp := span.lowVal == span.highVal && !span.lowExclude && !span.highExclude
	if !equalOp || !r.unique || span.lowVal == nil {
		return false
	}
	n, err := types.Compare(span.seekVal, span.lowVal)
	if err != nil {
		return false
	}
	return n == 0
}

开发者ID:huozhe3136，项目名称:tidb，代码行数:11，代码来源:index.go

示例18: isPointLookup

func (r *indexPlan) isPointLookup(span *indexSpan) bool {
	if span.lowExclude || span.highExclude || span.lowVal == nil || !r.unique {
		return false
	}
	n, err := types.Compare(span.seekVal, span.highVal)
	if err != nil {
		return false
	}
	// 'seekVal==highVal' means that 'seekVal==lowVal && lowVal==highVal'
	return n == 0
}

开发者ID:lovedboy，项目名称:tidb，代码行数:11，代码来源:index.go

示例19: builtinNullIf

// See https://dev.mysql.com/doc/refman/5.7/en/control-flow-functions.html#function_nullif
func builtinNullIf(args []interface{}, m map[interface{}]interface{}) (interface{}, error) {
	// nullif(expr1, expr2)
	// returns null if expr1 = expr2 is true, otherwise returns expr1
	v1 := args[0]
	v2 := args[1]

	if types.IsNil(v1) || types.IsNil(v2) {
		return v1, nil
	}

	if n, err := types.Compare(v1, v2); err != nil || n == 0 {
		return nil, err
	}

	return v1, nil
}

开发者ID:lovedboy，项目名称:tidb，代码行数:17，代码来源:control.go

示例20: Less

// Less implements sort.Interface Less interface.
func (t *orderByTable) Less(i, j int) bool {
	for index, asc := range t.Ascs {
		v1 := t.Rows[i].Key[index]
		v2 := t.Rows[j].Key[index]

		ret := types.Compare(v1, v2)
		if !asc {
			ret = -ret
		}

		if ret < 0 {
			return true
		} else if ret > 0 {
			return false
		}
	}

	return false
}

开发者ID:npk，项目名称:tidb，代码行数:20，代码来源:orderby.go

注：本文中的github.com/pingcap/tidb/util/types.Compare函数示例由纯净天空整理自Github/MSDocs等源码及文档管理平台，相关代码片段筛选自各路编程大神贡献的开源项目，源码版权归原作者所有，传播和使用请参考对应项目的License；未经允许，请勿转载。