On 1/19/07, Alexander B. <burbello3000@yahoo.com.br> wrote: I would like to know if is possible to replicate in postgres applying
binary logs (wal logs) like the same way is done on Oracle!!
Did anybody tried to do that?
Oracle doesn't use binary logs for replication, for regular snapshots it uses a "materialized log" -- which is nothing more than a table with a primary key and what type of change. If we are talking multi-master replication, then Oracle uses Advanced Queues (essentially another table) and pushes the data. All off this occurs over DB links.
As for binary (archived redo) logs in Oracle, they can be used for a Hot Standby. Which PostgreSQL also supports, as I understand it this is a new feature for 8.2.
I personally haven't investigated Slony, but I believe it functions similar.
Applying the simple ideia:
- for each archived Wal logs, transfer to slave server;
- after transfer, apply recover on postgres;
- repeat the steps above, all the time;
Again, this is a hot (warm in PostgreSQL) standby database. I don't think you can bring online a database in read only while it is actively applying the archived WAL logs.
--
Chad
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