Comments on: MySQL Replication Series (tip #1): what should be replicated and what should not be replicated?

By: Vanzan

Vanzan — Tue, 18 Aug 2009 02:55:11 +0000

Watchout with “replicate-do-db” when using mysql 4.1 !!
I must add a few precisions :
Because database names can contain commas (at least in 4.1), if you supply a comma separated list then the list will be treated as the name of a single database !! (not what we want at all)
To specify more than one database, use this option multiple times, once for each database.

Hope that helps

By: Sheeri

Sheeri — Wed, 23 Apr 2008 05:31:25 +0000

just some notes:

1) be careful with the binlog-do-db settings — you’re usually better off not constricting what the master sends, because what you don’t want replicated to database A today, you may want replicated to database B tomorrow. There are exceptions to this, certainly, but it’s not a bad rule to start with.

2) using “IF EXISTS” and “IF NOT EXISTS” can really help avoid replication issues with queries like “DROP TABLE IF EXISTS” since if it doesn’t exist, you don’t want replication to break, you just want the server to move on.

By: Artem Russakovskii

Artem Russakovskii — Tue, 22 Apr 2008 03:11:04 +0000

It’s also worth noting that starting with 5.1.21, you can also replicate only certain columns in tables.

If a table on a slave has less columns than the one onf the master, extra ones will be ignored (I’m assuming each query in the binlog will then just go through the filter to get those extra columns stripped off).

If the slave has more columns, they need to have default values.

http://dev.mysql.com/doc/refman/5.1/en/replication-features-differing-tables.html