The connection management architecture for both relational and procedural access to enterprise information systems is based on the J2EE Connector Architecture (JCA) specification. The connection manager, which pools and manages connections within an application server, is capable of managing connections obtained through both resource adapters that are defined by the JCA specification, and DataSources that are defined by the JDBC 2.0 Extensions Specification.
To make DataSource connections manageable by this connection manager that works only with resource adapters, WebSphere Application Server - Express provides its own resource adapter. From the connection manager point of view, JDBC DataSources and JCA connection factories look the same. Users of DataSources do not experience any programmatic or behavioral differences in their applications because of the underlying JCA architecture. JDBC users still configure and use DataSources according to the JDBC programming model.
Connection pooling
See this topic for information about database connection pools.Connection life cycle
This topic describes the life cycle of a database connection.Unshareable and shareable connections
Database connections can be shared by more than one component of an application. See this topic for considerations about whether to share database connections or not.Connection handles
This topic compares the characteristics of shared and unshared database connection references.Connections and transactions
See this topic for information about how connections behave in various transaction scopes.