Contents
concat()
A function for concatenating values
concat()
is a system function for concatenating arbitrary values into a text
string.
concat()
was added in PostgreSQL 9.1.
Usage
concat (val1
any
[,val2
any
[, ...] ] ) →text
To concatenate values using a delimiter, use concat_ws()
.
To aggregate string values from columns in a query, use string_agg()
.
Change history
- PostgreSQL 9.1
- added (commit 49b27ab5)
Examples
Basic usage example for concat()
:
postgres=# SELECT concat('foo', 'bar'); concat -------- foobar (1 row)
Differing data types can be concatenated:
postgres=# SELECT concat('foo', 1, 1.5, ARRAY[2,3], '{"4":"baz"}'::json); concat ------------------------- foo11.5{2,3}{"4":"baz"} (1 row)
NULL
values are ignored:
postgres=# SELECT concat('foo', NULL, 'bar'); concat -------- foobar (1 row)
An empty string will be returned if all provided values are NULL
:
postgres=# SELECT concat(NULL, NULL) IS NULL; ?column? ---------- f (1 row)
References
- PostgreSQL documentation: Other String Functions