Hibernate subquery problem with aggregate function - java

I'm trying to run this query within Hibernate (through JPA) but it throws
Caused by: java.lang.IllegalArgumentException: org.hibernate.hql.internal.ast.QuerySyntaxException: unexpected token: ( near line 1, column 32
Any way to make this work or make it better ? I would not want to use OR clause because the query is much slower when using that.
SELECT SUM(s) as sum FROM (
SELECT count (ID) AS s
FROM TABLE1 rr
WHERE rr.status = 0
AND (rr.risk = '1' AND rr.rate = '222' )
UNION ALL
SELECT count (ID) AS s
FROM TABLE1 rr
WHERE rr.status = 0
AND (rr.risk = '2' AND rr.open = '222' ))

With HQL queries, Hibernate ORM doesn't support subqueries in the FROM clause (you can use them in the WHERE clause).
If you cannot rewrite this query as HQL without the subquery (for performance reasons, for example), I think it's OK to run it on the db as a native SQL query:
String sqlQuery = ...;
session.createNativeQuery(sqlQuery).getSingleResult();

Related

Spring Data JPA - count number or results of query

I want to get the number of results of a query in Spring Data Jpa, using a non-native #Query method. It consists of a basic group by plus a having clause.
My plain query looks like this (analogous example):
select count(*) from (
select 1 from table t
where t.field_a = 1
group by t.id
having count(*) = 2) a;
Since Hibernate 5 does not allow subqueries in the form clause, I have to find a workaround for that. The only one I found is very inefficient as per the query plan:
select count(*) from table t
where t.field_a = 1 and
2 = (select count(*) from table temp where temp.id = t.id);
Is there a way to write a Spring Data JPA query that's as efficient as the first one? I can think of no solution rather than selecting the inner query and taking its size() in java, but that can produce issues due to a ton of redundant data passing through the network.
There is no easy solution to count the results of a subquery in JPA but the a workaround is proposed here https://arjan-tijms.omnifaces.org/2012/06/counting-rows-returned-from-jpa-query.html.
The principle is to build a native query based on the initial Jpa subselect query.
This does the job if you accept to count the elements in java !
Query q = em.createQuery(
"select 1 from table t where field_a = 1 " +
"group by t.id having count(*) = 2");
int count = q.getResultList().size();
(performances depending on the number of lines returned, but the projection is very light : 1)

Delete from table on same select same table mariadb using jpa

I need delete from table on operation of same table .JPA query is
DELETE FROM com.model.ElectricityLedgerEntity a
Where a.elLedgerid IN
(SELECT P.elLedgerid FROM
(SELECT MAX(b.elLedgerid)
FROM com.model.ElectricityLedgerEntity b
WHERE b.accountId='24' and b.ledgerType='Electricity Ledger' and b.postType='ARREARS') P );
I got this error:
with root cause org.hibernate.hql.ast.QuerySyntaxException: unexpected
token: ( near line 1, column 109 [DELETE FROM
com.bcits.bfm.model.ElectricityLedgerEntity a Where a.elLedgerid IN (
SELECT P.elLedgerid FROM ( SELECT MAX(b.elLedgerid) FROM
com.bcits.ElectricityLedgerEntity b WHERE b.accountId='24'
and b.ledgerType='Electricity Ledger' and b.postType='ARREARS') P ) ]
at
org.hibernate.hql.ast.QuerySyntaxException.convert(QuerySyntaxException.java:54)
at
org.hibernate.hql.ast.QuerySyntaxException.convert(QuerySyntaxException.java:47)
at
org.hibernate.hql.ast.ErrorCounter.throwQueryException(ErrorCounter.java:82)
at
org.hibernate.hql.ast.QueryTranslatorImpl.parse(QueryTranslatorImpl.java:284)
Same query is running on mysql terminal ,but this is not working with jpa .Can any one tell me how i can write this query using jpa .
I don't understand why do you use Pbefore the last parenthesis...
The following code is not enough ?
DELETE FROM com.model.ElectricityLedgerEntity a
Where a.elLedgerid IN
(SELECT MAX(b.elLedgerid)
FROM com.model.ElectricityLedgerEntity b
WHERE b.accountId='24' and b.ledgerType='Electricity Ledger' and
b.postType='ARREARS')
Edit for bypassing mysql subquery limitations :
The new error java.sql.SQLException: You can't specify target table 'LEDGER' for update in FROM clause
is known in mysql when you use it with JPA. It's one MySQL limitation.
A recent stackoverflow question about it
In brief, you cannot "directly" updated/deleted a table that you query in a select clause
Now I understand why your original query did multiple subqueries seemingly not necessary (while it was useful for mysql) and had a "special" syntax.
I don't know tricks to solve this problem in JPA (I don't use the MySQL DBMS for a long time now).
At your place, I would do two queries. The first where you select the expected max elLedgerid and the second where you could delete line(s) with the id retrieved in the previous query.
You should not have performance issues if your sql model is well designed, the sql indexes well placed and the time to access to the database is correct.
You cannot do this in a single query with Hibernate. If you want to delete the max row(s) with Hibernate you will have to do so in two steps. First, you can find the max entry, then you can delete using that value in the WHERE clause.
But the query you wrote should actually run as a raw MySQL query. So why don't you try executing that query as a raw query:
String sql = "DELETE FROM com.model.ElectricityLedgerEntity a " +
"WHERE a.elLedgerid IN (SELECT P.elLedgerid FROM " +
"(SELECT MAX(b.elLedgerid) FROM com.model.ElectricityLedgerEntity b " +
"WHERE b.accountId = :account_id AND b.ledgerType = :ledger_type AND " +
" b.postType = :post_type) P );";
Query query = session.createSQLQuery(sql);
query.setParameter("account_id", "24");
query.setParameter("ledger_type", "Electricity Ledger");
query.setParameter("post_type", "ARREARS");
Just want to extend existing answer:
In brief, you cannot "directly" updated/deleted a table that you query in a select clause
This was lifted with starting from MariaDB 10.3.1:
Same Source and Target Table
Until MariaDB 10.3.1, deleting from a table with the same source and target was not possible. From MariaDB 10.3.1, this is now possible. For example:
DELETE FROM t1 WHERE c1 IN (SELECT b.c1 FROM t1 b WHERE b.c2=0);

Hibernate 2 with MSSQL for ORDER BY

I have been working with Oracle and Postgre and recently switched to MS SQL 2012.
I use hibernate in my application and wherever I have used the Order by Criteria:
(criteria.addOrder(Order.asc("applicationId")));
It causes an error saying:
aggregate functions dont work.
Once I comment that line out my program works and data can be retrieved.
I'm using Hibernate 3.
Is there any way to order it through hibernate without this error?
edit..
This is one error I get,
Column "SKY.tcrent.RENTNO" is invalid in the ORDER BY clause because
it is not contained in either an aggregate function or the GROUP BY
clause.
Edit 2..
MY query
Query tcSchaduleQ = getSession().createQuery("SELECT SUM(tcs.dueAmount) FROM TrialCalculationSchedule tcs WHERE tcs.facilityId=:facilityId AND tcs.rentalNumber>:rentalNumber AND tcs.dueDate>:dueDate AND dueTypeId IN(:dueTypeId) ORDER BY tcs.rentalNumber ").setInteger("rentalNumber", facility.getPeriod() - noOfprePayments).setInteger("facilityId",facility.getFacilityId()).setDate("dueDate", date).setParameterList("dueTypeId", plist);
Number tcsAmt = (Number) tcSchaduleQ.uniqueResult();
and this is what hibernate generates in HQL
SELECT
SUM(tcs.dueAmount)
FROM
TrialCalculationSchedule tcs
WHERE
tcs.facilityId=:facilityId
AND tcs.rentalNumber>:rentalNumber
AND tcs.dueDate>:dueDate
AND dueTypeId IN(
:dueTypeId
)
ORDER BY
tcs.rentalNumber
and this is the SQL
select
SUM(trialcalcu0_.DUEAMT) as col_0_0_
from
SKYBANKSLFHP.tcrent trialcalcu0_
where
trialcalcu0_.FACID=?
and trialcalcu0_.RENTNO>?
and trialcalcu0_.DUEDATE>?
and (
trialcalcu0_.DUETYPEID in (
? , ?
)
)
order by
trialcalcu0_.RENTNO
Look Like you mix aggregate and non-aggregate expressions .If you are using any aggregate function like AVG() in Select query with some other non-aggregate then you must use Group By ..
Try something like this
createQuery("SELECT SUM(tcs.dueAmount) As DueAmount ...
If you are using Criteria then it should be like this
Criteria crit = sess.createCriteria(Insurance.class);
ProjectionList proList = Projections.projectionList();
proList.add(Projections.sum("investementAmount"));
crit.setProjection(proList);
List sumResult = crit.list();

How to count all groups returned by a group by query in JPQL?

If I have a group by query
Select e.field1, e.field2...
from Entity w
group by e.field1, e.field2...
How can I count the number of rows not using NativeQuery?
I need to do something like this:
select count(*) from
(Select e.field1, e.field2...
from Entity w
group by e.field1, e.field2...)
Is there any way to do with JPQL?
in oracle you can this hql
Select sum(count(*) - count(*) + 1)
from Entity e
group by e.field1, e.field2...
but dose not work in postgres
Derived tables are not supported in JPQL, so, the best way to do it is to run a native SQL query.
After all, there is a very good reason why both JPA and Hibernate offer support for SQL queries, don't you agree?

SQL subquery in Hibernate Query Language

I am new to HQL and I am working on subqueries.
I have the following SQL subquery:
select * from (
select * from table order by columnname
) as subquery
where columnvalue = 'somevalue';
I want to fire the query in HQL. I wrote the below code :
Result = session.createQuery("from (from table order by columnname) as subquery where columnvalue = :somevalue")
.setParameter(/*setting all parameters*/)
.list();
I am getting this exception:
QuerySyntaxException : unexpedted token :( line 1, column 10 [from (from ...)]
My SQL query is giving me correct results. How do I write it in HQL ?
I did not think HQL could do subqueries in the from clause
http://docs.jboss.org/hibernate/orm/3.3/reference/en/html/queryhql.html#queryhql-subqueries
note the sentence:
Note that HQL subqueries can occur only in the select or where clauses.
It will be better if you excute native SQL.

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