Re: Web application?

On Sáb 14 Jul 2001 04:59, Christopher Ostmo wrote: > > I use Postgres for a few functions that gather a lot of data and I don't > want that data slowing down my MySQL server. As an example of just > one of the speed differences, I had the data saving to both the > PostgreSQL server and the MySQL server (same physical machine) for > a short time. I had collected about 10,000 records in one table. > Deleting those records (DELETE * FROM table) in MySQL took less > than a second (MySQL destroys the table and recreates when you use > this command). The Postgress server took more than 10 minutes. As > a test, I recreated the data and deleted it in MySQL using "DELETE > FROM TABLE WHERE idfield LIKE '%%' (this causes MySQL to delete > records one at a time). It took about 7 seconds. Bad boy! Why didn't you use TRUNCATE <table-name> in PostgreSQL? That's because you are not an intense Postgres user, and makes you not know the added functions. One small question would be: have you tuned you're postgresql.conf file? have you tuned you're shared memory amount o semaphores? If you haven't done all three of these, you can't say much about PostgreSQL performance. > Every time I've done a comparison between the two on operations > involving large amounts of data, MySQL has come out ahead AT LEAST > five-fold. In many cases, it has come out much better than that. > > I'm admittedly not a big hardware performance expert, but I'm pretty > good with SQL and SQL optimization. How much of the ANSI-SQL do you use with MySQL, and how much would you be able to use with Postgres? > I also use PostgreSQL for the things that it does that MySQL does not > (commit/rollback mostly), but as of the 3.23.39, MySQL supports > transactions and it will support sub selects in the near future. Those > are the two missing features for which MySQL has taken nearly all of its > criticism. I don't think that I've heard anyone argue about it's raw speed > (when used properly of course). Thats not the worst thing I find in it. MySQL has referential integrity? How about locking for update of rows? You have to lock the whole table! Saludos... :-) -- Cualquiera administra un NT. Ese es el problema, que cualquiera administre. ----------------------------------------------------------------- Martin Marques | mmarques@unl.edu.ar Programador, Administrador | Centro de Telematica Universidad Nacional del Litoral -----------------------------------------------------------------