AILING} [remstr] FROM] str), TRIM([remstr
FROM] str)

Description
-----------

Returns the string str with all remstr prefixes or suffixes removed. If none
of the specifiers BOTH, LEADING, or TRAILING is given, BOTH is assumed. remstr
is optional and, if not specified, spaces are removed.

Returns NULL if given a NULL argument. If the result is empty, returns either
an empty string, or, from MariaDB 10.3.6 with SQL_MODE=Oracle, NULL.
SQL_MODE=Oracle is not set by default.

The Oracle mode version of the function can be accessed in any mode by using
TRIM_ORACLE as the function name.

Examples
--------

SELECT TRIM('  bar   ')\G
*************************** 1. row ***************************
TRIM('  bar   '): bar

SELECT TRIM(LEADING 'x' FROM 'xxxbarxxx')\G
*************************** 1. row ***************************
TRIM(LEADING 'x' FROM 'xxxbarxxx'): barxxx

SELECT TRIM(BOTH 'x' FROM 'xxxbarxxx')\G
*************************** 1. row ***************************
TRIM(BOTH 'x' FROM 'xxxbarxxx'): bar

SELECT TRIM(TRAILING 'xyz' FROM 'barxxyz')\G
*************************** 1. row ***************************
TRIM(TRAILING 'xyz' FROM 'barxxyz'): barx

From MariaDB 10.3.6, with SQL_MODE=Oracle not set:

SELECT TRIM(''),TRIM_ORACLE('');
+----------+-----------------+
| TRIM('') | TRIM_ORACLE('') |
+----------+-----------------+
|          | NULL            |
+----------+-----------------+

From MariaDB 10.3.6, with SQL_MODE=Oracle set:

SELECT TRIM(''),TRIM_ORACLE('');
+----------+-----------------+
| TRIM('') | TRIM_ORACLE('') |
+----------+-----------------+
| NULL     | NULL            |
+----------+-----------------+

URL: https://mariadb.com/kb/en/trim/https://mariadb.com/kb/en/trim/