Question

I know there is more than one question out there that matches this, but I am relatively new to mysql, and I can’t seem to make this work using sub quests or the USING key word, plus I find the mysql on line docs a complete mystery.

I started trying to build my DELETE query using a SELECT query as my base and was able to get all the rows that I wanted to delete:

select *
from writings_tags_link
join writing_tags on writing_tags.id = writings_tags_link.tag_id
where writing_tags.tag = 'tag one'

and then just replaced select all with DELETE so:

delete
from writings_tags_link
join writing_tags on writing_tags.id = writings_tags_link.tag_id
where writing_tags.tag = 'tag one'

I gather from both the error message and from other similar posts that you can’t use ‘ON’ to join tables in a delete query, you have to use USING or a sub query. The query I built with USING returns a really strange error, first the query:

DELETE
FROM writings_tags_link
USING writing_tags_link INNER JOIN writing_tags  
WHERE writing_tags.id = writings_tags_link.tag_id 
AND writing_tags.tag ='tag one'

error:

#1109 - Unknown table 'writings_tags_link' in MULTI DELETE

This table does exist, obviously, my original select query returned the desired results. Any help / explanation would be so very appreciated!

Please keep in mind, I’m only trying to delete the data in the linking table.

Answer 1

Your information is incorrect about requiring the use of the USING keyword in DELETE syntax when using JOINs – the documentation provides examples in the multi-delete section:

DELETE wtl
  FROM WRITINGS_TAGS_LINK wtl
  JOIN WRITING_TAGS wt ON wt.id = wtl.tag_id
 WHERE wt.tag = 'tag one'