When a transaction uses a SQL database, the connection string defined in the database XA resource definition associated with the region will, by default, be used to connect to that database. A database XA resource definition can be associated with a region at either the SIT or region startup file level. When specified in both the SIT and region start-up file, the region startup file takes precedence. However, if a database XA resource definition is defined for a PCT, that definition will be used in preference to the one associated with the region when the transaction is invoked. To associate a database XA resource definition with a PCT:
You must cold-start the region for the changes to take effect.