REGEXP_REPLACE

MariaDB starting with 10.0.5

REGEXP_REPLACE was introduced in MariaDB 10.0.5.

Syntax

REGEXP_REPLACE(subject, pattern, replace)

Description

REGEXP_REPLACE returns the string subject with all occurrences of the regular expression pattern replaced by the string replace. If no occurrences are found, then subject is returned as is.

The replace string can have backreferences to the subexpressions in the form \N, where N is a number from 1 to 9.

The function follows the case sensitivity rules of the effective collation. Matching is performed case insensitively for case insensitive collations, and case sensitively for case sensitive collations and for binary data.

The collation case sensitivity can be overwritten using the (?i) and (?-i) PCRE flags.

MariaDB 10.0.5 switched to the PCRE regular expression library for enhanced regular expression performance, and REGEXP_REPLACE was introduced as part of this enhancement.

MariaDB 10.0.11 introduced the default_regex_flags variable to address the remaining compatibilities between PCRE and the old regex library.

Examples

SELECT REGEXP_REPLACE('ab12cd','[0-9]','') AS remove_digits;
-> abcd

SELECT REGEXP_REPLACE('<html><head><title>title</title><body>body</body></htm>', '<.+?>',' ')
AS strip_html;
-> title  body

Backreferences to the subexpressions in the form \N, where N is a number from 1 to 9:

SELECT REGEXP_REPLACE('James Bond','^(.*) (.*)$','\\2, \\1') AS reorder_name;
-> Bond, James

Case insensitive and case sensitive matches:

SELECT REGEXP_REPLACE('ABC','b','-') AS case_insensitive;
-> A-C

SELECT REGEXP_REPLACE('ABC' COLLATE utf8_bin,'b','-') AS case_sensitive;
-> ABC

SELECT REGEXP_REPLACE(BINARY 'ABC','b','-') AS binary_data;
-> ABC

Overwriting the collation case sensitivity using the (?i) and (?-i) PCRE flags.

SELECT REGEXP_REPLACE('ABC','(?-i)b','-') AS force_case_sensitive;
-> ABC

SELECT REGEXP_REPLACE(BINARY 'ABC','(?i)b','-') AS force_case_insensitive;
-> A-C

Content reproduced on this site is the property of its respective owners, and this content is not reviewed in advance by MariaDB. The views, information and opinions expressed by this content do not necessarily represent those of MariaDB or any other party.

© 2021 MariaDB
Licensed under the Creative Commons Attribution 3.0 Unported License and the GNU Free Documentation License.
https://mariadb.com/kb/en/regexp_replace/