Re: Fw: Inner workings of a JOIN

Thank you for all of your answers and suggestions. I feel a lot more confident finishing my table designs -James

Fw: Inner workings of a JOIN

Meant to send this to the list. Christopher J. Noyes - Original Message - From: <[EMAIL PROTECTED]> To: "Roger Baklund" <[EMAIL PROTECTED]> Sent: Friday, May 27, 2005 9:55 PM Subject: Re: Inner workings of a JOIN Does it first create some sort of CROSS JO

Re: Inner workings of a JOIN

James Tu wrote: What does MySQL do internally when you perform a LEFT JOIN? You can read about it here: http://dev.mysql.com/doc/mysql/en/left-join-optimization.html > If you need more details, you could read the source... Let's say you have two tables: Table A has 1,000,000 rows Table B ha

Re: Inner workings of a JOIN

At http://dev.mysql.com/doc/mysql/en/explain.html the paragraph starting with "EXPLAIN returns a row of information for each table used in the SELECT statement" explains the process briefly. In general MySQL reads/finds rows while also satisfying other conditions. In your example below, if there's

Inner workings of a JOIN

What does MySQL do internally when you perform a LEFT JOIN? Let's say you have two tables: Table A has 1,000,000 rows Table B has 5,000 rows When you perform the following LEFT JOIN: Select A.*, B.* FROM A, B WHERE A.lastname = 'doe' AND A.id = B.id What does MySQL do