Ben Win Lue has asked for the wisdom of the Perl Monks concerning the following question:

Dear brethren,

I am trying to find a Perl fix for a Mysql problem. We are trying to migrate from Mysql 4.0something to Mysql 5.1.

Our application has grown organically and is using a couple of thousands of statement of which some have the ugly form:

select * from table1 a, table2 b left join table3 c on b.id = c.id where a.id = b.id
Statements like this are running with 4.0 smooth but cause errors with 5.1. The problem is caused by the mix of two join syntaxes: comma and "left join".
Since most of our statements are executed by a library function, we had the idea of identifying and fixing these statements on the fly.
The fix would be transforming the above statement to:
select * from table1 a inner join table2 b left join table3 c on b.id = c.id where a.id = b.id
which is not causing problems.

Did somebody run already in the same problem and has a neat regexp to identify and fix?
Is there a enlightened brother who could give me a hint for a regexp, that does the job?

Humbly yours

Replies are listed 'Best First'.
Re: Regexp for Mysql 5.1 join Problem
by CountZero (Bishop) on Jun 12, 2006 at 15:46 UTC
    Did you have a look at SQL::Statement. It can parse SQL statements into Perl OO.

    I would start from the OO-representation to transform it into the form you require.

    CountZero

    "If you have four groups working on a compiler, you'll get a 4-pass compiler." - Conway's Law