[pmwiki-users] Problem displaying MySQL queries

Nicolas Poulain nicolas at poulain.name
Fri Nov 18 04:59:36 CST 2011

2011/11/18 Petko Yotov <5ko at 5ko.fr>:
> There are no intentionally placed limits on the size of the wiki text, or of
> the output of a markup function. I have tested a markup producing huge output
> of 10+ megabytes -- at some point it will hit the PHP memory or time limit but
> I get a message telling me this.

Indeed, I have had memory time limit errors on an other pmwiki project
but here no error message occurs, even a php warning.

> If your output may be larger than 1 million bytes, and needs to be re-
> processed by the markup engine, you may need to increase the runtime value of
> pcre.backtrack_limit. Something like this in config.php:
>  @ini_set('pcre.backtrack_limit', 4000000); # 4MB
> On some installations, this may not work in config.php and you can only add it
> in the php.ini file.
> See http://fr.php.net/manual/en/pcre.configuration.php for more information.

As root, i will do it.

> Some custom markup may unintentionally wipe all page text, especially if you
> use it very early like at the 'fulltext' point. This can be tested by
> disabling custom markups or recipes one after another and refreshing the page,
> which at some point may appear correctly.

That seems very interesting. I'll dig this point and will let you know.

> P.S. I would be very careful if had to allow SQL queries from a wiki page, and
> even more if I had to trust http variables inside my SQL queries (I don't):
>  http://xkcd.com/327/

I am aware of this kind of trouble but it's an internal tool shared
only with a small group of users I can trust : they're allowed to read
and write the database.

Nicolas Poulain

More information about the pmwiki-users mailing list