Re: Views and subqueries
From: Lennart Jonsson <erik.lennart.jonsson_at_gmail.com>
Date: Tue, 13 Oct 2015 08:26:21 +0200
Message-ID: <mvi82g$j06$1_at_dont-email.me>
Date: Tue, 13 Oct 2015 08:26:21 +0200
Message-ID: <mvi82g$j06$1_at_dont-email.me>
On 2015-10-11 17:42, Stefan Ram wrote:
> It might be possible that I do not understand the
> implementation of views in MySQL!
>
> IIRC, in MySQL, views cannot contain subqueries.
Where have you heard that, do you have a reference? AFAIK it is possible to use subqueries in views
> And some
> parties say that views might degrade performance.
>
MySQL query rewriting and optimization seems rather limited. Even in trivial cases it sometimes fails to push predicates to the base tables resulting in unnessacary table scans. Not sure if this is what you mean though.
/Lennart
[...] Received on Tue Oct 13 2015 - 08:26:21 CEST