Re: Selecting (and accessing) from many tables

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On Tue, 2004-09-21 at 11:28, Tony Bowden wrote:
> This still sounds like premature optimisation to me. Most databases are
> really very efficient at this sort of thing (a single row select on a
> primary or foreign key).

While I understand what you and Carl are saying, and people often do
optimize before they should, Jesse is quite correct that 200 small
queries is nearly always slower than one large and correctly written
query.  He even has the large query already.  He's just trying to figure
out if he can use his Class::DBI objects to handle the data shuffling
once he has it from the database, rather than building a complex data
structure himself.

My answer is that unless you are happy with fetching a list of tracks
using a complex query and then letting them do additional queries for
the related CDs and Artists, Class::DBI is not any easier for this than
just building your own structure.  It may be worth investigating how
Hibernate or some other tools handle this scenario to see if there's
anything more that could be done.

- Perrin