Technical data

16 Managing JDBC Connectivity
16-6 Administration Guide
MultiPools
MultiPools aid in either:
n Load Balancing—pools are added without any attached ordering and are
accessed using a round-robin scheme. When switching connections, the
Connection Pool just after the last pool accessed is selected.
n High Availability—set up pools as an ordered list that determines the order in
which Connection Pool switching occurs. For example, the first pool on the list
is selected, then the second, etc.
All of the connections in a particular Connection Pool are identical; that is, they are
attached to a single database. The Connection Pools within a MultiPool may, however,
be associated with different DBMS. Read more about MultiPools in Programming
WebLogic JDBC at http://e-docs.bea.com/wls/docs61/jdbc/programming.html.
Data Sources
A Data Source object enables JDBC applications to obtain a DBMS connection from
a connection pool. Each Data Source object binds to the JNDI tree and points to a
connection pool or MultiPool. Applications look up the Data Source to get a
connection. Data Source objects can be defined with JTA (Tx Data Sources in the
Administration Console) or without JTA (Data Sources in the Administration
Console). You use Tx Data Source for distributed transactions. See “JDBC
Configuration Guidelines for Connection Pools, MultiPools and DataSources” on page
16-7 for more information about using Data Sources and Tx Data Sources.