-- 1st example
UPDATE files SET filepath = REPLACE(filepath,'path/to/search','path/to/replace');
 
-- 2nd example
UPDATE customers SET address = REPLACE(address,'_CODE_',postcode);

http://www.apphp.com/index.php?snippet=mysql-find-and-replace

MySQL has a handy and simple string function REPLACE() that allows table data with the matching string to be replaced by new string. This is useful if there is need to search and replace a text string which affects many records or rows, such as change of address, company name, URL or spelling mistake.

Find and Replace with MySQL

mysql, replace, find

MySQL