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.<init>(CriteriaJoinWalker.java:71)
at org.hibernate.loader.criteria.CriteriaLoader.<init>(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,
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;
and the magic is on groupby String. –
If someone needs to do it in grails it would be like:
projections {
groupProperty("id")
sqlGroupProjection(...)
rowCount()
}
Where sqlGroupProjection is available since 2.2.0
/**
* Adds a sql projection to the criteria
*
* @param sql SQL projecting
* @param groupBy group by clause
* @param columnAliases List of column aliases for the projected values
* @param types List of types for the projected values
*/
protected void sqlGroupProjection(String sql, String groupBy, List<String> columnAliases, List<Type> types) {
projectionList.add(Projections.sqlGroupProjection(sql, groupBy, columnAliases.toArray(new String[columnAliases.size()]), types.toArray(new Type[types.size()])));
}
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"}, new org.hibernate.type.Type[]{StandardBasicTypes.STRING}));
criteria.setProjection(projectionList);
criteria.List();
criteria.add(Restrictions.sqlRestriction("1=1 having count(*) = 2"));
来源:https://stackoverflow.com/questions/8605708/how-to-use-having-count-with-hibernate