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Golang BinaryOperation.IsIdentCompareVal方法代码示例

本文整理汇总了Golang中github.com/pingcap/tidb/expression.BinaryOperation.IsIdentCompareVal方法的典型用法代码示例。如果您正苦于以下问题:Golang BinaryOperation.IsIdentCompareVal方法的具体用法?Golang BinaryOperation.IsIdentCompareVal怎么用?Golang BinaryOperation.IsIdentCompareVal使用的例子?那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在github.com/pingcap/tidb/expression.BinaryOperation的用法示例。


在下文中一共展示了BinaryOperation.IsIdentCompareVal方法的2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,您的评价将有助于系统推荐出更棒的Golang代码示例。

示例1: filterBinOp

func (r *TableDefaultPlan) filterBinOp(ctx context.Context, x *expression.BinaryOperation) (plan.Plan, bool, error) {
	ok, name, rval, err := x.IsIdentCompareVal()
	if err != nil {
		return r, false, errors.Trace(err)
	}
	if !ok {
		return r, false, nil
	}
	if rval == nil {
		// if nil, any <, <=, >, >=, =, != operator will do nothing
		// any value compared null returns null
		// TODO: if we support <=> later, we must handle null
		return &NullPlan{r.GetFields()}, true, nil
	}

	_, tn, cn := field.SplitQualifiedName(name)
	t := r.T
	if tn != "" && tn != t.TableName().L {
		return r, false, nil
	}
	c := column.FindCol(t.Cols(), cn)
	if c == nil {
		return nil, false, errors.Errorf("No such column: %s", cn)
	}
	var seekVal interface{}
	if seekVal, err = types.Convert(rval, &c.FieldType); err != nil {
		return nil, false, errors.Trace(err)
	}
	spans := toSpans(x.Op, rval, seekVal)
	if c.IsPKHandleColumn(r.T.Meta()) {
		if r.rangeScan {
			spans = filterSpans(r.spans, spans)
		}
		return &TableDefaultPlan{
			T:         r.T,
			Fields:    r.Fields,
			rangeScan: true,
			spans:     spans,
		}, true, nil
	} else if r.rangeScan {
		// Already filtered on PK handle column, should not switch to index plan.
		return r, false, nil
	}

	ix := t.FindIndexByColName(cn)
	if ix == nil { // Column cn has no index.
		return r, false, nil
	}
	return &indexPlan{
		src:     t,
		col:     c,
		unique:  ix.Unique,
		idxName: ix.Name.O,
		idx:     ix.X,
		spans:   spans,
	}, true, nil
}
开发者ID:lovedboy,项目名称:tidb,代码行数:57,代码来源:from.go

示例2: filterBinOp

func (r *TableDefaultPlan) filterBinOp(ctx context.Context, x *expression.BinaryOperation) (plan.Plan, bool, error) {
	ok, name, rval, err := x.IsIdentCompareVal()
	if err != nil {
		return r, false, err
	}
	if !ok {
		return r, false, nil
	}
	if rval == nil {
		// if nil, any <, <=, >, >=, =, != operator will do nothing
		// any value compared null returns null
		// TODO: if we support <=> later, we must handle null
		return &NullPlan{r.GetFields()}, true, nil
	}

	_, tn, cn := field.SplitQualifiedName(name)
	t := r.T
	if tn != "" && tn != t.TableName().L {
		return r, false, nil
	}
	c := column.FindCol(t.Cols(), cn)
	if c == nil {
		return nil, false, errors.Errorf("No such column: %s", cn)
	}

	ix := t.FindIndexByColName(cn)
	if ix == nil { // Column cn has no index.
		return r, false, nil
	}

	var seekVal interface{}
	if seekVal, err = types.Convert(rval, &c.FieldType); err != nil {
		return nil, false, err
	}
	return &indexPlan{
		src:     t,
		col:     c,
		idxName: ix.Name.O,
		idx:     ix.X,
		spans:   toSpans(x.Op, rval, seekVal),
	}, true, nil
}
开发者ID:kevinhuo88888,项目名称:tidb,代码行数:42,代码来源:from.go


注:本文中的github.com/pingcap/tidb/expression.BinaryOperation.IsIdentCompareVal方法示例由纯净天空整理自Github/MSDocs等开源代码及文档管理平台,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。