Making PHP faster?

I'm using PHP to load data into a PostgresQL database. The script works fine but it is a bit slow. It's taking about 30 minutes to load about 15,000 items. This is mainly because of all the error checking and many redundant queries I am running. This program is a one-off thing. Are there any simple ways for me to make PHP run faster? I'm already using persistent DB connections. I was thinking along the lines increasing it's memory usage, turning off error checking, getting it to optimize the code on the fly, etc ...? Thanks! Jc