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The transaction-type attribute is used to specify whether the entity managers provided by the
entity manager factory for the persistence unit must be JTA entity managers or resource-local entity
managers. The value of this element is JTA or RESOURCE_LOCAL. A transaction-type of JTA assumes that a JTA data source will be provided. It is provided either as specified by the jta-data-source element or provided by the container. In general, in Java EE environments, a transaction-type of RESOURCE_LOCAL assumes that a non-JTA datasource will be provided. In a Java EE environment, if this element is not specified, the default is JTA. In a Java SE environment, if this element is not specified, a default of RESOURCE_LOCAL may be assumed.
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