Please take back-up of your current database before running query

update wp_posts set post_content = replace(post_content, 'http://localhost/dpsi', '');

You can change the table name ‘post_content’ if you want to replace any other table
for eg. you want to replace url from guid field of table wp_posts, than query will be

update wp_posts set guid = replace(guid, 'http://localhost/dpsi', '');

Run this query in phpmyadmin, select the table before run query

Query synatx: Find & Replace Data in MySQL

update [table_name] set [field_name] = replace([field_name],'[string_to_find]','[string_to_replace]');