On Wed, Nov 23, 2011 at 8:09 PM, Nikolas Stevenson-Molnar <nik.mol...@consbio.org> wrote: > What database are you using? You should be able to find information in > the documents about the locking behavior for that database. Compare that > with the operations your running and determine whether they would result > in an exclusive lock. > > From your pseudocode, it looks like you're performing a possibly-lengthy > select, followed by lengthy calculations (not involving database > operations), and then a (presumably) quick save. AFAIK, databases never > lock when doing selects, so depending on the nature of your > calculations, you should be fine. >
MySQL will always lock tables for writes when reading from them. Therefore, any long running query on a mysql table will result in updates to that table being locked out. The easiest way around this is with hardware. Use a master-slave DB setup, and perform your long reads on the slave(s), and all your writes on the master. Cheers Tom -- You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to django-users@googlegroups.com. To unsubscribe from this group, send email to django-users+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/django-users?hl=en.
