Re: [Phplib-users] Caching MySQL queries

[Donncha O C. <don...@tr...>]

"nathan r. hruby" wrote:
> 
> On Fri, 26 Oct 2001, Donncha O Caoimh wrote:
> 
> > That's the simple explanation. I serialize the array and base64_encode
> > it before caching it and seperate each record by a "\n". When I read it
> > back I split the cache by "\n" and eval() the correct row. Not the best
> > way of doing it but it's the most obvious way I thought of and the
> > quickest to see if it'd work :)
> >
> 
> I picked up on this late, so please shoot me if I'm straying or this has
> been covered.
> 
> base64 encoding increases the size of stored vaules by a lot which could
> be part of the problem when working with large result sets.  Unless you
> need base64 I'd say just to just serialize the mysql result arrays, add
> whatever delim you nedd and addslash() them then jsut stripslash(),
> split() and eval()

Did that and it's easier to debug the cache now.. mimencode just makes
sure that things are def. not 8 bit characters..

> 
> Question is what kind of metadata does the cache have to make sure the
> data is fresh and to determine a hit (looking back, md5 sums of the
> original sql query statement.. i see that should work) and where does this
> cache live?  If it's living in a db, well, then what's the point except to
> speed up very complex queries.  Now if it's living in a shmem ssegment,
> well, that's just darn fast..  With something like Zend cache, you may be
> able to use a file and let *that* cache engine take care of it too, if you
> don't feel like coding your own shmem functions

I haven't even looked at that yet. All I'm doing is setting an arbitrary
timeout on every query. The cache gets stored in /tmp at the moment.
Again, I'm trying to get it to work first before I do anything exotic
with it. And also allowing for dropping in other caching scripts too.

Donncha.