How to make JOIN query use index?

Question

I have two tables:

CREATE TABLE `articles` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `title` varchar(1000) DEFAULT NULL,
  `last_updated` datetime DEFAULT NULL         


        

Answer 1

You can use influence MySQL to use KEYS or INDEXES

For

• Ordering, or
• Grouping, or
• Join

For extra information, follow this link. I intended to use this for joining (i.e. USE INDEX FOR JOIN (My_Index) but it didn't work as expected. Removing the FOR JOIN part sped up my query significantly, from more than 3.5 hours, to 1-2 seconds. Simply because MySQL was forced to use the right index.