PHP Nested Loop

davidjwest

I've written a fairly simple piece of PHP that includes 3 nested loops (for loops) and it's now extremely slow, taking several minutes to process.

There's nothing very complex going on, total of about 100 MySQL updates in there, is there a known issue with nested loops in PHP, Google doesn't seem to think so.

Anyone got any ideas, I can post the code if you want to look at it.

RobTang

It doesn't really sound that efficient.

and 100 update statements sounds like a lot ouside of some form of transformation process, which isn't really PHPs job.

Time how long each section takes to execute and see your bottleneck really is. But its almost certainly your SQL code.

davidjwest

The code performs 10,000 MySQL inserts and that takes 2 seconds, it then comes to the 3 nested loops and takes several minutes, including less than 100 MySQL updates.

Code isn't as efficient as it could be but I don't understand why the huge increase in time, maybe there's some other issue.

DVardysShadow

I know very little about this, but let us assume your code does not contain any bug. The kinds of things I would be looking for are

• Wrong order of nesting, making more work
• Hopping across tables and back, not allowingg caching to speed things up
• Unnecessary operations to open and close table and so forth

Mr_Oink

Chances are, to give you help you'll need to cough up some of that code. Personally, I would try here:
http://www.codingforums.com/forumdisplay.php?f=6