Optimize PHP/MYSQL Export Script - PHP/MYSQL Expert Needed

I have an existing PHP export script that manipulates some data and then exports the data into a csv file.

The script exports a survey. Each survey typically has around 20 questions (the question vary slightly from survey to survey). Each survey can have around 5000 entrants. The way the questions and answers are stored is by record since the questions are different for each survey.

The problem is some exports take 45 minutes and fail (I need to run them via the command line to complete them).

The problem is the script seems to have been written inefficiently. Instead of the SQL being written to pull in all data in one pass (ie SELECT [url removed, login to view],max(if(field_id=97, field_value,' ')) as '#1', max(if(field_id=98, field_value,' ')) as '#2',,,,,,,,,

group by [url removed, login to view]) and then do some parsing (the actual SQL takes around 8 seconds to run and produce the 5000 entrant records inc column format) in the way I am thinking), it instead does something else in multiple passes and takes 45 minutes to produce csv file. What I am suggesting would need to be written so it is dynamic (every contest has different questions), but I think it would work.

I need a strong MYSQL and php coder to come up with a better script so it runs much faster.

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AJAX MySQL PHP

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