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Golang KeyspaceTerm.Keys方法代码示例

本文整理汇总了Golang中github.com/couchbase/query/algebra.KeyspaceTerm.Keys方法的典型用法代码示例。如果您正苦于以下问题:Golang KeyspaceTerm.Keys方法的具体用法?Golang KeyspaceTerm.Keys怎么用?Golang KeyspaceTerm.Keys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/couchbase/query/algebra.KeyspaceTerm的用法示例。


在下文中一共展示了KeyspaceTerm.Keys方法的3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: selectScan

func (this *builder) selectScan(keyspace datastore.Keyspace, node *algebra.KeyspaceTerm,
	limit expression.Expression) (op plan.Operator, err error) {
	keys := node.Keys()
	if keys != nil {
		switch keys := keys.(type) {
		case *expression.ArrayConstruct:
			this.maxParallelism = util.MaxInt(1, len(keys.Operands()))
		case *algebra.NamedParameter, *algebra.PositionalParameter:
			this.maxParallelism = 0
		default:
			this.maxParallelism = 1
		}

		return plan.NewKeyScan(keys), nil
	}

	this.maxParallelism = 0 // Use default parallelism for index scans

	secondary, primary, err := this.buildScan(keyspace, node, limit)
	if err != nil {
		return nil, err
	}

	if secondary != nil {
		return secondary, nil
	} else {
		return primary, nil
	}
}
开发者ID:mschoch,项目名称:query,代码行数:29,代码来源:build_scan.go

示例2: VisitKeyspaceTerm

func (this *builder) VisitKeyspaceTerm(node *algebra.KeyspaceTerm) (interface{}, error) {
	node.SetDefaultNamespace(this.namespace)
	keyspace, err := this.getTermKeyspace(node)
	if err != nil {
		return nil, err
	}

	if this.subquery && this.correlated && node.Keys() == nil {
		return nil, errors.NewSubqueryMissingKeysError(node.Keyspace())
	}

	scan, err := this.selectScan(keyspace, node, this.limit)
	if err != nil {
		return nil, err
	}

	this.children = append(this.children, scan)

	if this.coveringScan == nil {
		fetch := plan.NewFetch(keyspace, node)
		this.subChildren = append(this.subChildren, fetch)
	}

	return nil, nil
}
开发者ID:pkdevboxy,项目名称:query,代码行数:25,代码来源:build_select_from.go

示例3: buildJoinScan

func (this *builder) buildJoinScan(keyspace datastore.Keyspace, node *algebra.KeyspaceTerm, op string) (
	datastore.Index, expression.Covers, error) {
	indexes, err := allIndexes(keyspace)
	if err != nil {
		return nil, nil, err
	}

	var pred expression.Expression
	pred = expression.NewIsNotNull(node.Keys().Copy())
	dnf := NewDNF()
	pred, err = dnf.Map(pred)
	if err != nil {
		return nil, nil, err
	}

	subset := pred
	if this.where != nil {
		subset = expression.NewAnd(subset, this.where.Copy())
		subset, err = dnf.Map(subset)
		if err != nil {
			return nil, nil, err
		}
	}

	formalizer := expression.NewFormalizer()
	formalizer.Keyspace = node.Alias()
	primaryKey := expression.Expressions{
		expression.NewField(
			expression.NewMeta(expression.NewConstant(node.Alias())),
			expression.NewFieldName("id", false)),
	}

	sargables, err := sargableIndexes(indexes, pred, subset, primaryKey, dnf, formalizer)
	if err != nil {
		return nil, nil, err
	}

	minimals, err := minimalIndexes(sargables, pred)
	if err != nil {
		return nil, nil, err
	}

	if len(minimals) == 0 {
		return nil, nil, errors.NewNoIndexJoinError(node.Alias(), op)
	}

	return this.buildCoveringJoinScan(minimals, node, op)
}
开发者ID:jmptrader,项目名称:query,代码行数:48,代码来源:build_join_index.go


注:本文中的github.com/couchbase/query/algebra.KeyspaceTerm.Keys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。