I would like to know how to update a table, with values from another table, by the trick is I need to set a limit because I have thousands of rows to update, and PHPmyadmin can't handle that load. ( I dont have direct access to the server )
My table structure looks like this
wp_postmeta
meta_id,
post_id,
meta_key,
meta_value
wp_map
oldmap, newmap
What I need to do is join the two tables on wp_postmeta.meta_value and wp_map.oldmap, and update the wp_postmeta.meta_value with wp_map.newmap.
Here is my current query, but I need to add a LIMIT of 100 to the query, as I'm splitting the query up into smaller chunks so PHPMyAdmin can process.
UPDATE wp_postmeta
INNER JOIN wp_map
ON wp_map.oldmap = wp_postmeta.meta_value
SET wp_postmeta.meta_value = wp_map.newmap;
I read about creating a subquery, but couldn't find any relevant examples, so if someone could steer me in the right direction or provide a working example it would be greatly appreciated.