To answer this question, we need to understand the purpose of the EJB Query Language (EJB QL) and how it is used.
Option A) to enhance the SQL96 standard with additional options for complex relationships
This option is incorrect. EJB QL is not used to enhance the SQL96 standard. It is a separate query language specifically designed for working with Enterprise JavaBeans (EJBs).
Option B) instead of the findByPrimaryKey() method, to define alternative selection criteria
This option is incorrect. EJB QL is not used as an alternative to the findByPrimaryKey() method. The findByPrimaryKey() method is used to retrieve an entity bean based on its primary key, while EJB QL is used for querying entities based on various criteria.
Option C) to specify a concrete implementation for the find and select methods of CMP entity beans
This option is correct. EJB QL is used to specify the queries for the find and select methods of Container Managed Persistence (CMP) entity beans. These methods are used to retrieve data from the underlying database using the specified query.
Option D) for accessing User Defined data types and Stored Procedures in the database.
This option is incorrect. EJB QL is not used for accessing User Defined data types and Stored Procedures in the database. It is primarily used for querying and retrieving data from entity beans.
Therefore, the correct answer is C) to specify a concrete implementation for the find and select methods of CMP entity beans.