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Golang SelectStatement.HasDistinct方法代码示例

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


在下文中一共展示了SelectStatement.HasDistinct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: NewLocalMapper

// NewLocalMapper returns a mapper for the given shard, which will return data for the SELECT statement.
func NewLocalMapper(shard *Shard, stmt *influxql.SelectStatement, chunkSize int) *LocalMapper {
	m := &LocalMapper{
		shard:     shard,
		stmt:      stmt,
		chunkSize: chunkSize,
		cursors:   make([]*tagSetCursor, 0),
	}

	m.rawMode = (stmt.IsRawQuery && !stmt.HasDistinct()) || stmt.IsSimpleDerivative()
	return m
}
开发者ID:pdf,项目名称:influxdb,代码行数:12,代码来源:mapper.go

示例2: plan

// Plan creates an execution plan for the given SelectStatement and returns an Executor.
func (q *QueryExecutor) plan(stmt *influxql.SelectStatement, chunkSize int) (Executor, error) {
	shards := map[uint64]meta.ShardInfo{} // Shards requiring mappers.

	// Replace instances of "now()" with the current time, and check the resultant times.
	stmt.Condition = influxql.Reduce(stmt.Condition, &influxql.NowValuer{Now: time.Now().UTC()})
	tmin, tmax := influxql.TimeRange(stmt.Condition)
	if tmax.IsZero() {
		tmax = time.Now()
	}
	if tmin.IsZero() {
		tmin = time.Unix(0, 0)
	}

	for _, src := range stmt.Sources {
		mm, ok := src.(*influxql.Measurement)
		if !ok {
			return nil, fmt.Errorf("invalid source type: %#v", src)
		}

		// Build the set of target shards. Using shard IDs as keys ensures each shard ID
		// occurs only once.
		shardGroups, err := q.MetaStore.ShardGroupsByTimeRange(mm.Database, mm.RetentionPolicy, tmin, tmax)
		if err != nil {
			return nil, err
		}
		for _, g := range shardGroups {
			for _, sh := range g.Shards {
				shards[sh.ID] = sh
			}
		}
	}

	// Build the Mappers, one per shard.
	mappers := []Mapper{}
	for _, sh := range shards {
		m, err := q.ShardMapper.CreateMapper(sh, stmt.String(), chunkSize)
		if err != nil {
			return nil, err
		}
		if m == nil {
			// No data for this shard, skip it.
			continue
		}
		mappers = append(mappers, m)
	}

	if stmt.IsRawQuery && !stmt.HasDistinct() {
		return NewRawExecutor(stmt, mappers, chunkSize), nil
	}
	return NewAggregateExecutor(stmt, mappers), nil
}
开发者ID:rnubel,项目名称:influxdb,代码行数:52,代码来源:query_executor.go

示例3: PlanSelect

// Plan creates an execution plan for the given SelectStatement and returns an Executor.
func (q *QueryExecutor) PlanSelect(stmt *influxql.SelectStatement, chunkSize int) (Executor, error) {
	var shardIDs []uint64
	shards := map[uint64]meta.ShardInfo{} // Shards requiring mappers.

	// It is important to "stamp" this time so that everywhere we evaluate `now()` in the statement is EXACTLY the same `now`
	now := time.Now().UTC()

	// Replace instances of "now()" with the current time, and check the resultant times.
	stmt.Condition = influxql.Reduce(stmt.Condition, &influxql.NowValuer{Now: now})
	tmin, tmax := influxql.TimeRange(stmt.Condition)
	if tmax.IsZero() {
		tmax = now
	}
	if tmin.IsZero() {
		tmin = time.Unix(0, 0)
	}

	for _, src := range stmt.Sources {
		mm, ok := src.(*influxql.Measurement)
		if !ok {
			return nil, fmt.Errorf("invalid source type: %#v", src)
		}

		// Build the set of target shards. Using shard IDs as keys ensures each shard ID
		// occurs only once.
		shardGroups, err := q.MetaClient.ShardGroupsByTimeRange(mm.Database, mm.RetentionPolicy, tmin, tmax)
		if err != nil {
			return nil, err
		}
		for _, g := range shardGroups {
			for _, sh := range g.Shards {
				if _, ok := shards[sh.ID]; !ok {
					shards[sh.ID] = sh
					shardIDs = append(shardIDs, sh.ID)
				}
			}
		}
	}

	// Sort shard IDs to make testing deterministic.
	sort.Sort(uint64Slice(shardIDs))

	// Build the Mappers, one per shard.
	mappers := []Mapper{}
	for _, shardID := range shardIDs {
		sh := shards[shardID]

		m, err := q.ShardMapper.CreateMapper(sh, stmt, chunkSize)
		if err != nil {
			return nil, err
		}
		if m == nil {
			// No data for this shard, skip it.
			continue
		}
		mappers = append(mappers, m)
	}

	// Certain operations on the SELECT statement can be performed by the AggregateExecutor without
	// assistance from the Mappers. This allows the AggregateExecutor to prepare aggregation functions
	// and mathematical functions.
	stmt.RewriteDistinct()

	if (stmt.IsRawQuery && !stmt.HasDistinct()) || stmt.IsSimpleDerivative() {
		return NewRawExecutor(stmt, mappers, chunkSize), nil
	} else {
		return NewAggregateExecutor(stmt, mappers), nil
	}
}
开发者ID:yuanwr,项目名称:kapacitor,代码行数:70,代码来源:query_executor.go


注:本文中的github.com/influxdb/influxdb/influxql.SelectStatement.HasDistinct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。