Database agnostic query to get the row number based on the primary key

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Let country be a table in an RDBMS system. Its columns are intuitive. Therefore, I do not go in depth nor they are required to know.

I needed SQL statements like the following at many places through out the application while using JPA (through EclipseLink / Hibernate).

MySQL :

SELECT rownum 
FROM   (SELECT @rownum := @rownum + 1 AS rownum, tbl.country_id 
        FROM   country tbl, (SELECT @rownum := 0) t 
        ORDER  BY tbl.country_id DESC)t 
WHERE  country_id =? 

Oracle (using window analytic functions) :

SELECT row_num 
FROM   (SELECT ROW_NUMBER() 
               OVER (ORDER BY country_id DESC) AS row_num, country_id 
        FROM   country 
        ORDER  BY country_id DESC) 
WHERE  country_id = ?

This native statement is required to be executed directly through the use of the createNativeQuery() method as follows.

entityManager.createNativeQuery("Above Query")
             .setParameter(1, id)
             .getResultList();

These statements are meant to return a row number based on the given primary key value as set by using the setParameter() method.

They are not database agnostic. Does there exist any database agnostic stuff in JPA?

_{I do not use the getSingleResult() method to get a single (scalar) value as this method would unnecessarily throw an exception, if a query statement returned none or multiple rows accidently.}

asked 20 secs ago

Tiny

2,428

Database agnostic query to get the row number based on the primary key