web server - Borland Technical Publications

Container-managed data access support
Important
Note
Important
You specify your own optimized SQL in the Borland proprietary deployment descriptor,
ejb-borland.xml. The XML grammar is identical to that found in ejb-jar.xml, except that
the element is replaced with a element. This proprietary element
contains a SQL-92 statement (not an EJB-QL statement) that is used to access the
database instead of the CMP engine-generated SQL.
The SELECT clause for this statement must be identical to the SELECT clause generated
by the Borland CMP engine.
Subsequent clauses are user-optimized. The ordering of the fields in the SELECT clause
is proprietary to the CMP engine and therefore must be preserved.
For example:
EmployeeBean
...
findWealthyEmployees
SELECT E.DEPT_NO, E.EMP_NO, E.FIRST_NAME, E.FULL_NAME,
E.HIRE_DATE, E.JOB_CODE, E.JOB_COUNTRY,
E.JOB_GRADE, E.LAST_NAME, E.PHONE_EXT, E.SALARY
FROM EMPLOYEE E WHERE E.SALARY > 200000
...
The extensive SELECT statement reflects the type of SQL generated by the CMP engine.
When the CMP engine encounters an EJB-QL statement in the ejb-jar.xml
deployment descriptor, it checks ejb-borland.xml to see if there is any user SQL
provided in the same bean's descriptor.
If none is present, the CMP engine generates its own SQL and executes it.
If the ejb-borland.xml descriptor does contain a query element, it uses the SQL within
the tags instead.
The element in ejb-borland.xml does not replace the element in the
standard ejb-jar.xml deployment descriptor. If you want to override the CMP engine's
SQL, you must provide the elements in both descriptors.
Container-managed data access support
For CMP, the Borland EJB Container supports all data types supported by the JDBC
specification, including types beyond those supported by JDBC.
The following table shows the basic and complex types supported by the Borland EJB
Container:
Basic types: boolean Boolean byte Byte char Character
double Double float Float int Integer
long Long short Short String java.sql.Date
BigDecimal
java.util.Date
byte[]
java.sql.Time
java.sql.TimeStamp
Chapter 17: EJB-QL and Data Access Support 159