Problem with ON clause in MySQL 5

[Debbie-Leigh]

Hi,

My hoster has recently updated their servers to the all new version 5s of PHP and MySQL, which has caused a bit of a problem with some of my queries. It seems to be an obscure one and I can't seem to find anything in the manuals about it.

The query that I'm using is:

     SELECT t1.my_col1
          , t2.my_col2
          , t3.my_col3
          , t4.my_col4
       FROM offer      t1
          , price_type t2
  LEFT JOIN processor  t3
         ON t3.processor_id  = ''
  LEFT JOIN currency   t4
         ON t4.currency_id   = t1.currency_id
      WHERE t1.offer_id      = 1
        AND t1.price_type_id = t2.price_type_id

The problem is with the ON of the second LEFT JOIN. If I run it as it is i.e. comparing the two columns, it says 'Unknown column t1.currency_id', but the currency_id column definitely exists on the offer table. However, when I change that line to t4.currency_id = 1 or t1.currency_id = 1, the query works fine. The query also works fine in v4.

Obviously, I can't run it using t1.currency_id = 1, so could anyone tell me whether there was a change in the way ON clauses work between v4 and v5 of MySQL, as I can't find any indiction in the manuals about this?

Debbie