Simon Riggs wrote: > > On Wed, 2008-08-13 at 15:38 +0200, Markus Wanner wrote: > > > Simon Riggs wrote: > > > Classification of Replication Techniques > > > > Thanks for your classifications. It helps a great deal to clarify. > > > > > Type 2 is where you ship the WAL (efficient) then use it to reconstruct > > > SQL (flexible) and then apply that to other nodes. It is somewhat harder > > > than type 1, but requires less infrastructure (IMHO). Definitely > > > requires less data shipping from Primary node, so very possibly more > > > efficient. > > > > What leads you to that conclusion? AFAICT a logical format, specifically > > designed for replication is quite certainly more compact than the WAL > > (assuming that's what you mean by "less data"). > > Possibly, but since we are generating and writing WAL anyway that's not > a completely fair comparison. > > > Which of IBM's and Oracle's products are you referring to? > > IBM DB2 HADR, QReplication. > Oracle Streams 10g+, Data Guard Logical and Physical Standby > All of which I've personally used, except for Oracle Streams10g, which I > investigated thoroughly for a client about 4 years ago.
I think doing the WAL streaming and allowing a read-only slave is enough work to keep Simon busy for quite some time. I don't understand why the logical issue is being discussed at this stage --- let's get the other stuff done first. -- Bruce Momjian <[EMAIL PROTECTED]> http://momjian.us EnterpriseDB http://enterprisedb.com + If your life is a hard drive, Christ can be your backup. + -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
