Contents
left()
A function returning characters from the left of a string
left()
is a system function returning the specified number characters from the left of the provided string.
left()
was added in PostgreSQL 9.1.
Usage
left (string
text
,n
integer
) →text
If n
is negative, returns all but the last n
characters.
Change history
- PostgreSQL 9.1
- added (commit 49b27ab5)
Examples
Basic usage example for left()
:
postgres=# SELECT left('foobar', 3); left ------ foo (1 row)
Providing a negative value:
postgres=# SELECT left('foobarbaz', -3); left -------- foobar (1 row)
Usage with a non-Latin character set:
postgres=# SELECT left('ほげほげ', 2); left ------ ほげ (1 row)
References
- PostgreSQL documentation: Other String Functions