Thread: Re: [GENERAL] BIG Data and Perl
At 09:52 AM 15-10-1999 -0500, Andy Lewis wrote: >I've got a fairly good size database that has in one table around 50,000 >records in it. > >It starts of and processes the first 300-400 rows fast and then gets >slower in time and eventually just quits. It'll run for about 4-6 hours >before it quits. > >Any idea what may be going on here? Maybe you're running out of memory. Your perl script may be reading too much into memory. When using the perl DBI module, I get the impression that the perl script reads in all the results when you do $cursor->execute I don't know if there are any ways around this. It can be a bit inconvenient if the result is large ;). Cheerio, Link.
This is slightly unrelated (well, maybe more than slightly) but what is the advantage to using cursors over normal SELECT statements? I know from experience that just using an execute("SELECT...") and fetchrow_array doesn't go wild with memory usage, as long as you remember to close your statement handles. At 11:48 PM 10/17/99, Lincoln Yeoh wrote: >At 09:52 AM 15-10-1999 -0500, Andy Lewis wrote: >>I've got a fairly good size database that has in one table around 50,000 >>records in it. >> >>It starts of and processes the first 300-400 rows fast and then gets >>slower in time and eventually just quits. It'll run for about 4-6 hours >>before it quits. >> >>Any idea what may be going on here? > >Maybe you're running out of memory. Your perl script may be reading too >much into memory. > >When using the perl DBI module, I get the impression that the perl script >reads in all the results when you do >$cursor->execute > >I don't know if there are any ways around this. It can be a bit >inconvenient if the result is large ;). > >Cheerio, > >Link. > > >************ >
I've identified the problem. Its actually with a regex that I wrote. I'm in the process of re-writting that. Thanks. Andy On Mon, 18 Oct 1999, Lincoln Yeoh wrote: > At 09:52 AM 15-10-1999 -0500, Andy Lewis wrote: > >I've got a fairly good size database that has in one table around 50,000 > >records in it. > > > >It starts of and processes the first 300-400 rows fast and then gets > >slower in time and eventually just quits. It'll run for about 4-6 hours > >before it quits. > > > >Any idea what may be going on here? > > Maybe you're running out of memory. Your perl script may be reading too > much into memory. > > When using the perl DBI module, I get the impression that the perl script > reads in all the results when you do > $cursor->execute > > I don't know if there are any ways around this. It can be a bit > inconvenient if the result is large ;). > > Cheerio, > > Link. > > > ************ >