influxdb/tsdb/cursor.go

package tsdb

import "github.com/influxdata/influxdb/query"

// EOF represents a "not found" key returned by a Cursor.
const EOF = query.ZeroTime

// Cursor represents an iterator over a series.
type Cursor interface {
	SeekTo(seek int64) (key int64, value interface{})
	Next() (key int64, value interface{})
	Ascending() bool
}
Add tsdb.MultiCursor This commit adds a cursor that wraps multiple `tsdb.Cursor` objects and streams them out as one cursor. The multi-cursor automatically dedupes keys by using the first cursor specified in the argument list. 2015-08-07 23:02:29 +00:00			`package tsdb`

Separate the query engine into a separate package This change provides a clear separation between the query engine mechanics and the query language so that the language can be parsed and dealt with separate from the query engine itself. 2017-08-15 19:24:22 +00:00			`import "github.com/influxdata/influxdb/query"`
Support negative timestamps in the query engine Negative timestamps are now supported. We also now refuse two nanoseconds that are at the edge of the minimum time window. One of the nanoseconds we do not accept is because we need MinInt64 to be used for some internal comparisons in the TSM engine and it was causing an underflow when we subtracted one from the minimum time. The second is so we can have one minimum time that signifies the default minimum that nobody can write to (so we can implicitly rewrite the timestamp on aggregate queries) but still use the explicit timestamp if it is given to us by the user. We aren't able to tell the difference between if the user provided it or if it was implicit without those values being different. If the default minimum time is used with an aggregate query, we rewrite the time to be the epoch for backwards compatibility since we believe that's more important than supporting that extra nanosecond. 2016-08-25 17:52:39 +00:00
refactor cursor 2015-09-20 22:27:22 +00:00			`// EOF represents a "not found" key returned by a Cursor.`
Separate the query engine into a separate package This change provides a clear separation between the query engine mechanics and the query language so that the language can be parsed and dealt with separate from the query engine itself. 2017-08-15 19:24:22 +00:00			`const EOF = query.ZeroTime`
refactor cursor 2015-09-20 22:27:22 +00:00
rename direction to ascending. 2015-09-16 21:04:37 +00:00			`// Cursor represents an iterator over a series.`
			`type Cursor interface {`
rename Cursor.Seek() to Cursor.SeekTo() 2015-09-22 19:20:53 +00:00			`SeekTo(seek int64) (key int64, value interface{})`
refactor cursor 2015-09-20 22:27:22 +00:00			`Next() (key int64, value interface{})`
rename direction to ascending. 2015-09-16 21:04:37 +00:00			`Ascending() bool`
Replace cursor direction with a type 2015-09-02 21:42:34 +00:00			`}`