Connection Fail-over

Question

My database may be replicated to multiple servers, in the event that a connection fails to the primary server, my class should try the same statement on the next context in an ordered list.
Any advice on errors to watch for to know the connection is broken (versus an error resulting from the query itself)?
Any advice on executing a query for one connection, and then if it fails, executing the same statement on a different connection? I am hoping to keep the fail-over logic encapsulated in a simple to use class so that all the classes that call stored procedures don't have to contain the logic.
I primarily use stored procedures, but have an occasional text sql query too.
Many thanks in advance!
Darcy

Answer 1

the best way to test this would probably be to establish a connection to the database, and then stop the database and try to execute a query against it and see what SQLException gets thrown, then you can watch for that one.
also, if you are using database pooling (or even if you aren't) you can validate each connection object you create with something like "select getDate()" or something basic that should return at least one row. if you don't get a row back or if you get an exception you know something is wrong with the database and you can then move to the next one.