Question

I have a complicated HQL query.

I would like to access the Oracle specific rownum column value as part of my returned results. How do I write my query (and/or change my hbm.xml) to support this?

What I have tried so far does not work:

modifying my hbm.xml

<property name='rownum' type='int' update='false' insert='false' generated='never'/> 

and a query such as:

'select dog.rownum from Dog as dog where ...' 

But I get java.sql.SQLException: ORA-01747: invalid user.table.column, table.column, or column specification

I suspect I might need to mix some sql with my complex hql query… suggestions welcome. Thanks.

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Some background:

• http://ronfrancis.wordpress.com/2007/10/16/dont-forget-an-order-by-for-pagination-queries/
• hibernate uses oracle’s rownum ‘under the hood’ to paginate results.

Answer 1

ROWNUM doesn’t belong to any table, so your query should be:

'select rownum from Dog as dog where ...' 

For example:

SQL> select emp.ename, rownum from emp;  ENAME          ROWNUM ---------- ---------- SMITH               1 ALLEN               2 WARD                3 JONES               4 MARTIN              5 BLAKE               6 CLARK               7 SCOTT               8 KING                9 TURNER             10