Spring JPA Specification : How to sort on aggregate function using specification

Question

Error is thrown when we are trying to sort on aggregated column COUNT.

For Example : Requirement is to form below query using specification. But, it is not returning single entity as result. Rather, it's join of tables.

Sort on SQL Query required using Specification :

Select DISTINCT ss.studentId.name, ss.studentId.department , COUNT (DISTINCT ss.subjectId.id)" +
            "FROM SubjectStudent  ss " +
            "left outer join ss.studentId sd  " +
            "left outer join ss.subjectId su "+
            "GROUP BY  ss.studentId.cve, ss.subjectId.id " +
            "ORDER BY ss.studentId.department

So, here how can we sort on aggregate column COUNT using specification?

in sql you can directly use the selected column number. e.g select name, count(*) from table group by name order by 2 — Sandesh, Nov 28 '18 at 11:36
Solution : criteriaBuilder.having(<>) whenever we want to put condition on aggregate functions using specification — Vaibhav Sawant, Dec 05 '18 at 13:46

score 1 · Accepted Answer · answered Dec 05 '18 at 13:50

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Solution : criteriaBuilder.having(<>) whenever we want to put condition on aggregate functions using specification

answered Dec 05 '18 at 13:50

Vaibhav Sawant

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Spring JPA Specification : How to sort on aggregate function using specification

1 Answers1