[drupal-devel] MySQL 3, MySQL 4 and MySQL 5

[K B]

Making something reliant on InnoDB is a big mistake. Though they are
better in many aspects, they are not available everywhere.

The caveat here is that MySQL will let you say "CREATE TABLE ...
Type=InnoDB" even if you DO NOT have InnoDB functionality in the back
end.

I tested this myself on a server running Mandrake Linux, and the
behavior is what I outlined above: no error given, nothing. The user
could be fooled into thinking they are running InnoDB while they are
not.

I would imagine that MySQL will allow you to have FOR UPDATE on MyISAM
tables, and will simply ignore it, like it does in many other
statements it does not support.

On servers that you have control of, you must load a package called
MySQL-MaxDB to get Inno support.

Since most people are on shared hosting, this would be a source of
great confusion, and perhaps serious problems (assume that locking is
happening while it is not, ...etc.)

So, we have to be careful with mandating InnoDB. If we do, it has to
be an option, not mandatory.
---
Gerhard says:

On Mon, 2 May 2005, Karoly Negyesi wrote:

> > Do you have experience with using InnoDB? Does it have other
> > (dis)advantages? Should we consider to use InnoDB for some tables?
>
> No. Slow.

I think this is too narrow minded. If InnoDB would give us some usefull
features, we should consider to try using them and do benchmarks. I can
imagine that for some tables being a bit slow isn't a real problem, but
row based locking might be a significant improvement. For example we
could have a "locks" table that looks similar to this: