Master failover

Question

I have setup a replication group with 4 nodes (1 master, 3 replica nodes).
1. When there is a failure in current master node, the election is triggered. Is it possible to specify which replica node should be selected as next master either programmatically or through some configuration?
2. I want to specify the isolation level for my read operations as READ_COMMITTED. The API allows to specify this only if I use a Transaction object. How can I set isolation level without using a transaction?
primaryKey.get(Transaction, PK, LockMode)
Thanks
PS

Answer 1

1. When there is a failure in current master node, the election is triggered. Is it possible to specify which replica node should be selected as next master either programmatically or through some configuration?You can use rep_set_priority() to assign an integer priority value to each site in your replication group. Larger integer values indicate more desirable election winners. There is a special priority value of 0 that indicates that a site should never win an election.
An election determines a winner first by determining the client with the most recent log records. If clients are tied in this respect, the election chooses the client with this highest priority value. If both log records and client priorities are tied, a winner is selected at random.
2. I want to specify the isolation level for my read operations as READ_COMMITTED. The API allows to specify this only if I use a Transaction object. How can I set isolation level without using a transaction?
primaryKey.get(Transaction, PK, LockMode)I'm not an expert in transactions, but I do not see a way you can achieve READ_COMMITTED isolation level 2 guarantees without transactions. But I have asked some of our transaction experts about this, and one of us will respond either to confirm this or let you know about anything I have missed.
Paula Bingham
Oracle