Defining a JDBC Datasource

When executing a web based application, the developer has the possibility of using a JDBC Datasource to connect to database.

Using a JDBC datasource means that the Application server is in charge of the database connection, the GeneXus implementation is not used.

In order to use this feature, enable the Use Datasource for Web Based Applications Property.

Advantages and disadvantages of using a JDBC Datasource

Advantages

• It is possible to monitor the application from J2EE server instead of changing client.cfg.
• Some datasources have important features like connection monitoring (in order to pull it off when killed).
• It is possible to use JTA.
• It is possible to change connection parameters on run-time (in Before Connect event).
• You can configure that BC's TRN are managed by the container when Call Protocol property is set to Enterprise Java Bean value.

Disadvantages

• Some pools doesn't recycle connections.
• It doesn't keep a memory cache of prepared sentences (or it is done only one per request and all are killed at the end).

See also

JDBC Datasource in Tomcat 8 (or higher)
Tomcat
Websphere
Weblogic
Oracle App Server 10g
JDBC Datasource on JBoss