leftjoin

Type of operation: Join

Description

Temporal left join, adding new columns in the output dataset.

Usage

leftjoin [ @targetDataset ], [ predicate_1, predicate_2, ... ], [ columnbinding_1, columnbinding_2, ... ]

Argument	Type	Optional	Repeatable	Restrictions
@targetDataset	dataset	yes	no	dataset
predicate	bool	yes	yes	none
columnbinding	expression	yes	yes	none

Options

Option	Type	Meaning
ntrhs	bool
ntrhs	bool

Accelerable

leftjoin is always accelerable if the input is accelerable. A dataset that only uses accelerable verbs can be accelerated, making queries on the dataset respond faster.

Examples

leftjoin on([email protected]), hostname:@host.name

Temporal left join with dataset ‘host’, and extract the ‘name’ column from that ‘host’ table, calling the new column ‘hostname’ in the output.