On 5/2/12 10:58 PM, Jim Nasby wrote: > On 4/29/12 6:03 AM, Simon Riggs wrote: >>> The DML-WITH-LIMIT-1 is required to do single logical updates on tables >>> > with non-unique rows. >>> > And as for any logical updates we will have huge performance problem >>> > when doing UPDATE or DELETE on large table with no indexes, but >>> > fortunately this problem is on slave, not master;) >> While that is possible, I would favour the do-nothing approach. By >> making the default replication mode = none, we then require a PK to be >> assigned before allowing replication mode = on for a table. Trying to >> replicate tables without PKs is a problem that can wait basically. >> > > Something that a in-core method might be able to do that an external one > can't would be to support a method of uniquely identifying rows in > tables with no PK's. A gross example (that undoubtedly wouldn't work in > the real world) would be using TID's. A real-world implementation might > be based on a hidden serial column.
-- Josh Berkus PostgreSQL Experts Inc. http://pgexperts.com -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
