Albe Laurenz ha scritto: > Ottavio Campana wrote: >> I'm writing a python script to update some tables in a db. My >> problem is >> that I need to lock a couple of tables, perform several operations and >> read the corresponding output. >> >> I was thinking about lock in exclusive mode, but in the >> documentation I >> found that it is valid only in a transaction. But since I need to >> execute a command and read the output and so forth, I think I >> cannot use >> a transaction. >> >> What would you use to lock the table? > > What makes you think that you "need to lock a couple of tables"? the point is that for each table I have a copy I previously made and I want to create an incremental backup. My problem is that I don't want the original table to change, so I lock it. I admin that exclusive lock is probably too much. Does share mode block inser/update/delete but allows reading? Thanks. PS: By the way, I just discovered that with python psycopg2 the cursor is wrapped in a transaction, so locking works. So the problem is only the correct lock level.
Attachment:
signature.asc
Description: OpenPGP digital signature
