This works but you have to take advantage of the period at the end.
CREATE TABLE `forumpost` (
`name` varchar(255) DEFAULT NULL
) ENGINE=InnoDB
mysql> select name from forumpost;
+----------------------------+
| name |
+----------------------------+
| An auditor drives an audi. |
| An auditor drives a volvo. |
+----------------------------+
UPDATE forumpost SET name = REPLACE(name, 'audi.', 'toyota.') WHERE name LIKE '%audi.';
Query OK, 1 row affected (0.20 sec)
Rows matched: 1 Changed: 1 Warnings: 0
mysql> select * from forumpost;
+------------------------------+
| name |
+------------------------------+
| An auditor drives an toyota. |
| An auditor drives a volvo. |
+------------------------------+
Otherwise you need to look into options by using SUBSTRING and LOCATE
Just trying to help....
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