HOW to use HAVING COUNT(*) with hibernate

问题:

I need to create a query and I need COUNT(*) and HAVING COUNT(*) = x.

I'm using a work around that uses the CustomProjection class, that I downloaded somewhere.

This is the SQL that I try to achieve:

select count(*) as y0_, this_.ensayo_id as y1_ from Repeticiones this_ inner join Lineas linea1_ on this_.linea_id=linea1_.id where this_.pesoKGHA>0.0 and this_.nroRepeticion=1 and linea1_.id in (18,24) group by this_.ensayo_id having count(*) = 2

This is the code, where I use the Projection Hibernate class:

critRepeticion.setProjection(Projections.projectionList()                 .add( Projections.groupProperty("ensayo") )                 .add( CustomProjections.groupByHaving("ensayo_id",Hibernate.LONG,"COUNT(ensayo_id) = "+String.valueOf(lineas.size()))                 .add( Projections.rowCount() )                 );

The error is:

!STACK 0 java.lang.NullPointerException at org.hibernate.criterion.ProjectionList.toSqlString(ProjectionList.java:50) at org.hibernate.loader.criteria.CriteriaQueryTranslator.getSelect(CriteriaQueryTranslator.java:310) at org.hibernate.loader.criteria.CriteriaJoinWalker.(CriteriaJoinWalker.java:71) at org.hibernate.loader.criteria.CriteriaLoader.(CriteriaLoader.java:67) at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1550) at org.hibernate.impl.CriteriaImpl.list(CriteriaImpl.java:283) at ar.com.cse.cseagro.controller.RepeticionController.buscarEnsayo(RepeticionController.java:101)

If I comment the line with CustomProjections class, the query work, but I don't get the HAVING COUNT(*) filter in the SQL ...

Basically the query try to retrieve, in a master - detail schema, all the master records where a list of details are simultaneously present, like if you want tho know "which invoices have both products, A and B".

That why if I got 3 items in the IN clause, I need to use HAVING COUNT = 3 clause.

Any idea or suggestion? Best regards,

回答1:

I figured out the problem. I replace CusotmProjections class, with:

.add( Projections.sqlGroupProjection("ensayo_id", groupBy , alias, types));

where groupBy, alias and types are:

 String groupBy = "ensayo_id" + " having " + "count(*) = " + String.valueOf(lineas.size());  String[] alias = new String[1];   Alias[0] = "ensayo_id";   Type[] types = new Type[1];   types[0] = Hibernate.INTEGER;

回答2:

Here is my sample, it works fine, maybe useful :

My sql query :

select COLUMN1, sum(COLUMN2) from MY_TABLE group by COLUMN1 having sum(COLUMN2) > 1000;

And Criteria would be :

 Criteria criteria = getCurrentSession().createCriteria(MyTable.Class);   ProjectionList projectionList = Projections.projectionList();   projectionList.add(Projections.property("column1"), "column1");   projectionList.add(Projections.sqlGroupProjection("sum(column2)  sumColumn2 ", "COLUMN1 having sum(COLUMN2) > 1000" , new String[]{"sumColumn2"},