Delete with Join in MySQL

Question

Here is the script to create my tables:

CREATE TABLE clients (
   client_i INT(11),
   PRIMARY KEY (client_id)
);
CREATE TABLE projects (
   project_id INT(         


        

Answer 1

One solution is to use subquery

DELETE FROM posts WHERE post_id in (SELECT post_id FROM posts p
INNER JOIN projects prj ON p.project_id = prj.project_id 
INNER JOIN clients c on prj.client_id = c.client_id WHERE c.client_id = :client_id 
);

The subquery returns the ID that need to be deleted; all three tables are connected using joins and only those records are deleted that meets the filter condition (in yours case i.e. client_id in the where clause).