Something in the back of my head is saying that DBD::MySQL does not truely support SQL placeholders, and instead emulates them. So it doesn't surprise me that you saw better performance by not using them.

After tooling around the net for a little while, I didn't find anything more conclusive on DBD::MySQL placeholders being emulated or not. I know the older versions of DBD::MySQL didn't support it. Here is a link to that; Tim Bunce talking about DBD::MySQL, look in the PARAMETER BINDING section for this ...

Neither engine supports placeholders, but the DBD::mysql and DBD::mSQL drivers provide full emulation. Question marks are used as placeholders, as in ...

I also found this more recent link on the DBI Dev message board. They are talking about named placeholders, but in it this person mentions that ...

DBD::mysql does the placeholder parsing in the DBD driver so you can substitue a placeholder for anything, including the whole of the SQL statement if you so desire (with a little bit of trickery (such as binding as an integer)).

I would be very interested to know for sure who/where/what does the placeholder parsing with DBD::MySQL. And if it would really make a difference anyway.

-stvn

In reply to Re: mod_perl was hosed by a bind variable by stvn
in thread mod_perl was hosed by a bind variable by phildog

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