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MySQL string replace

I have a column containing urls (id, url):

http://www.example.com/articles/updates/43
http://www.example.com/articles/updates/866
http://www.example.com/articles/updates/323
http://www.example.com/articles/updates/seo-url
http://www.example.com/articles/updates/4?something=test

I'd like to change the word "updates" to "news". Is it possible to do this with a script?

I keep coming here for years to find the order of the REPLACE(...) parameters. If this question is ever deleted, I'll no longer be able to do my job. Thanks!

r
rogerdpack
UPDATE your_table
SET your_field = REPLACE(your_field, 'articles/updates/', 'articles/news/')
WHERE your_field LIKE '%articles/updates/%'

Now rows that were like

http://www.example.com/articles/updates/43

will be

http://www.example.com/articles/news/43

http://www.electrictoolbox.com/mysql-find-replace-text/


Quick question, is it really needed to have the "WHERE" clause?
@JohnCrawford According to the article in the link: "You don't necessarily have to add the WHERE LIKE clause at the end, because if the text to find isn't there the row won't be updated, but it should speed things up."
WHERE clause gives you specific control over what gets replaced. Without one every row will be checked and potentially data replaced if a match is found.
I believe in this case the WHERE is useless because a LIKE '%%' does not use any indexes, if there were other parts in that WHERE, for example something like date_added > '2014-07-01' it might have helped
I always come here for reference when I need to replace something in mysql
o
onteria_

Yes, MySQL has a REPLACE() function:

mysql> SELECT REPLACE('www.mysql.com', 'w', 'Ww');
    -> 'WwWwWw.mysql.com'

http://dev.mysql.com/doc/refman/5.0/en/string-functions.html#function_replace

Note that it's easier if you make that an alias when using SELECT

SELECT REPLACE(string_column, 'search', 'replace') as url....

As long as the OP's updates only shows up once in the string, then this would work. Otherwise you're stuck with direct string manipulation which is a real pain in MySQL. At that point it'd be easier to write a one-off script to select the fields, manipulation in the client, then write back.
N
Nicholas Shanks

The replace function should work for you.

REPLACE(str,from_str,to_str)

Returns the string str with all occurrences of the string from_str replaced by the string to_str. REPLACE() performs a case-sensitive match when searching for from_str.


S
Shiwangini

You can simply use replace() function.

Example:

with where clause-

update tableName set columnName=REPLACE(columnName,'from','to') where condition;

without where clause-

update tableName set columnName=REPLACE(columnName,'from','to');

Note: The above query if for update records directly in table, if you want on select query and the data should not be affected in table then can use the following query-

select REPLACE(columnName,'from','to') as updateRecord;

R
RafaSashi

In addition to gmaggio's answer if you need to dynamically REPLACE and UPDATE according to another column you can do for example:

UPDATE your_table t1
INNER JOIN other_table t2
ON t1.field_id = t2.field_id
SET t1.your_field = IF(LOCATE('articles/updates/', t1.your_field) > 0, 
REPLACE(t1.your_field, 'articles/updates/', t2.new_folder), t1.your_field) 
WHERE...

In my example the string articles/news/ is stored in other_table t2 and there is no need to use LIKE in the WHERE clause.


G
Ganesh Giri

The REPLACE function is very handy to search and replace text in a table such as updating obsolete URL, correcting a spelling mistake, etc.

  UPDATE tbl_name 
    SET 
        field_name = REPLACE(field_name,
            string_to_find,
            string_to_replace)
    WHERE
        conditions;