Categories:

String & Binary Functions (Matching/Comparison)

REPLACE

Removes all occurrences of a specified substring, and optionally replaces them with another substring.

Syntax

REPLACE( <subject> , <pattern> [ , <replacement> ] )
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Arguments

subject

The subject is the string in which to do the replacements. Typically, this is a column, but it can be a literal.

pattern

This is the substring that you want to replace. Typically, this is a literal, but it can be a column or expression. Note that this is not a “regular expression”; if you want to use regular expressions to search for a pattern, use the REGEXP_REPLACE function.

replacement

This is the value used as a replacement for the pattern. If this is omitted, or is an empty string, then the REPLACE function simply deletes all occurrences of the pattern.

Returns

The returned value is the string after all replacements have been done.

Usage notes

  • If replacement is not specified, subject is returned with all occurrences of pattern removed.

  • If replacement is specified, subject is returned with all occurrences of pattern replaced by replacement.

  • If any of the arguments is a NULL, the result is also a NULL.

Note

Only occurrences in the original subject are considered. A pattern that occurs in the result is not removed/replaced.

Collation details

The collation specifications of all input arguments must be compatible.

This function does not support the following collation specifications:

  • pi (punctuation-insensitive).

  • cs-ai (case-sensitive, accent-insensitive).

Examples

Replace the string down with the string up:

SELECT REPLACE('down', 'down', 'up');
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+-------------------------------+
| REPLACE('DOWN', 'DOWN', 'UP') |
|-------------------------------|
| up                            |
+-------------------------------+

Replace the substring Athens in the string Vacation in Athens with the substring Rome:

SELECT REPLACE('Vacation in Athens', 'Athens', 'Rome');
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+-------------------------------------------------+
| REPLACE('VACATION IN ATHENS', 'ATHENS', 'ROME') |
|-------------------------------------------------|
| Vacation in Rome                                |
+-------------------------------------------------+

Replace the substring bc in the string abcd with an empty substring:

SELECT REPLACE('abcd', 'bc');
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+-----------------------+
| REPLACE('ABCD', 'BC') |
|-----------------------|
| ad                    |
+-----------------------+

Replace the values in a table with new values.

Create and populate a table:

CREATE OR REPLACE TABLE replace_example(
  subject VARCHAR(10),
  pattern VARCHAR(10),
  replacement VARCHAR(10));

INSERT INTO replace_example VALUES
  ('old car', 'old car', 'new car'),
  ('sad face', 'sad', 'happy'),
  ('snowman', 'snow', 'fire');
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Replace strings in a value with a specified replacement:

SELECT subject,
       pattern,
       replacement,
       REPLACE(subject, pattern, replacement) AS new
  FROM replace_example
  ORDER BY subject;
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+----------+---------+-------------+------------+
| SUBJECT  | PATTERN | REPLACEMENT | NEW        |
|----------+---------+-------------+------------|
| old car  | old car | new car     | new car    |
| sad face | sad     | happy       | happy face |
| snowman  | snow    | fire        | fireman    |
+----------+---------+-------------+------------+

The output shows the following replacements:

  • The string old car was replaced by the string new car.

  • In the string sad face, the substring sad was replaced by the substring happy to create the new string happy face.

  • In the string snowman, the substring snow was replaced by the substring fire to create the new string fireman.