0017609: Use of join without an ON clause

(0055931)
support (administrator)
14-02-15 22:42

interesting. Have you done any tests to see if there's a speed difference?

(0055932)
support (administrator)
14-02-15 22:43

hang on, there is an ON in that query, isn't there?

(0055933)
duncanc (developer)
15-02-15 12:23

There are three joins, the last of which has an ON condition, the first two do not. But you have put the ON conditions in the WHERE clause of the query and it looks like mysql uses those to avoid the cartesian product that I was thinking about.

But it is a really confusing approach and likely to be error prone by not putting the conditions in the JOIN itself

I suggest moving conditions to the joins

join %s as u on listuser.userid = u.id
join %s as listmessage on listuser.listid = listmessage.listid

(0055950)
michiel (manager)
27-02-15 09:38

https://github.com/michield/phplist/commit/ba5a576c7d6e0406b6f5d69d067505e406d30be5 [^]

Notes
(0055931) support (administrator) 14-02-15 22:42	interesting. Have you done any tests to see if there's a speed difference?

(0055932) support (administrator) 14-02-15 22:43	hang on, there is an ON in that query, isn't there?

(0055933) duncanc (developer) 15-02-15 12:23	There are three joins, the last of which has an ON condition, the first two do not. But you have put the ON conditions in the WHERE clause of the query and it looks like mysql uses those to avoid the cartesian product that I was thinking about. But it is a really confusing approach and likely to be error prone by not putting the conditions in the JOIN itself I suggest moving conditions to the joins join %s as u on listuser.userid = u.id join %s as listmessage on listuser.listid = listmessage.listid

(0055950) michiel (manager) 27-02-15 09:38	https://github.com/michield/phplist/commit/ba5a576c7d6e0406b6f5d69d067505e406d30be5 [^]

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