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jpql left join fetch not returning results for like

In a spring mvc app using hibernate and MySQL, I have written the following query method to return a list of names with patients:
#SuppressWarnings("unchecked")
public Collection<Person> findPersonByLastName(String ln) throws DataAccessException{
Query query = this.em.createQuery("SELECT DISTINCT pers FROM rimPerson pers left join fetch pers.names nm WHERE nm.family LIKE :lnm");
query.setParameter("lnm", ln);
return query.getResultList();
}
This is producing the following hibernate sql:
Hibernate:
select distinct
person0_.hppid as hppid1_340_0_,
names1_.HJID as HJID1_89_1_,
person0_2_.classCode_HJID as classCod2_339_0_,
person0_1_.administrativeGenderCode_HJID as administ2_341_0_,
person0_1_.birthTime_HJID as birthTim3_341_0_,
names1_.DELIMITER_ as DELIMITE2_89_1_,
names1_.FAMILY as FAMILY3_89_1_,
names1_.named_entity_hppid as named5_89_1_,
names1_.SUFFIX as SUFFIX4_89_1_,
names1_.name_entity_HJID as name9_340_0__,
names1_.HJID as HJID1_89_0__
from
rim_person person0_ inner join rim_living_subject person0_1_ on person0_.hppid=person0_1_.hppid
inner join rim_entity person0_2_ on person0_.hppid=person0_2_.hppid
inner join rim_infrastructure_root person0_3_ on person0_.hppid=person0_3_.hppid
left outer join EN names1_ on person0_.hppid=names1_.name_entity_HJID
where names1_.FAMILY like ?
When I call the above jpql method with the following command, it returns zero results:
this.myappService.findPersonByLastName("");
I also get zero results when I cut and past the above generated hibernate code into the MySQL command line client and replace ? with ''.
If, however, I remove the where names1_.FAMILY like ? from the hibernate generated sql above and place the shortened sql into the MySQL command line client, I get four results, eachof which has a value for the lastname field.
How can I change the jpql so that it generates a hibernate query that returns the four results when `` is passed as the empty string parameter? I want the result set to include every result when the user gives empty input, but to give filtered results when the user types in any given text input.

The typical reason that like fails to do what you think it ought to do is to forget to put a wildcard in the pattern string. For example, if you want to match all user names that begin with 'Code' you must do something like name like 'Code%', NOT name like 'Code'. You can control exactly what your predicate matches with careful placement of %s in your string.
Try this to see all entities no matter what the value in family:
this.myappService.findPersonByLastName("%");
It is kinda cheesy to have the caller of findPersionByLastName have to put in the % wildcard. A better implementation is to have the caller specify which last name they are looking for, and then have the code that constructs the query put the wildcard in the right place. When you are looking for last names, you might do something like this:
query.setParameter("lnm", "%" + ln);
That would match anything that ends with the parameter that is passed to the method.

Hibernate returns list of nulls although executed SQL returns values

I'm using hibernate as an ORMapper. I want to execute an actually rather simple hql query:
SELECT a
FROM Foo a
WHERE a.status = :A0status
ORDER BY a.bookingTypeCode ASC,
a.priority ASC
This hql query is then converted into a sql query which looks something like this:
select a.*
from Foo a
where a.status='A'
order by a.bookingtypecode ASC,
a.priority ASC
When I execute the sql on the oracle database using the Oracle SQL Developer I get 17 rows returned. However, when I execute the hql query (using the list method of a Query I get a list of 17 elements that are all null. Although the number of elements is correct, not a single one of the elements is actually loaded.
This is the way I create and execute my query:
// the hql query is stored in the hqlQuery variable;
// the parameter are stored in a Map<String, Object> called params
Query hQuery = hibSession.createQuery(hqlQuery);
for (Entry<String, Object> param : params.entrySet()) {
String key = param.getKey();
Object value = param.getValue();
hQuery.setParameter(key, value);
}
List<?> result = hQuery.list();
Does anyone know what might be the problem here?
Update 1
I've recently upgrade from hibernate 3.2 to 4.3.5. Before the upgrade everything worked fine. After the upgrade I get this error.

I've set the Log level of hibernate to TRACE and found the problem. It was actually a mapping/logic/database error. The primary key consisted of two columns (according to the entity class) and one of these columns was nullable. However a primary key can never be nullable. Therefore hibernate always returned null.

If you have not set a custom (and buggy) ResultTransformer, my second best guess is that your debugger is lying to you. Does you code actually receives a list of null?
Also make sure to test with the code you are showing is. Too many times, people simplify things and the devil is in the details.

This error is happening to me. MySQL query browser works, but in hibernate of 7 columns and only one column always came with all null fields. I checked all the ids and they were not null. The error was in the construction of SQL Native. I had to change the way of writing it. Ai worked.
SELECT c.idContratoEmprestimo as idContratoEmprestimo,
c.dtOperacao as dataOperacao,
p.cpf as cpf,
p.nome as nome,
(Select count(p2.idParcelaEmprestimo) from EMP_PARCELA p2 where p2.valorPago > 0 and p2.dtPagamento is not null
and p2.idContratoEmprestimo = c.idContratoEmprestimo and p2.mesCompetencia <= '2014-08-01') as parcelasPagas, c.numeroParcelas as numeroParcelas,
pe.valorPago as valorParcela
FROM EMP_CONTRATO c inner join TB_PARTICIPANTE_DADOS_PLANO AS pp on pp.idParticipantePlano = c.idParticipantePlano
inner join TB_PARTICIPANTE as p on p.id = pp.idParticipante
inner join TB_PARTICIPANTE_INSTITUIDOR as pi on pi.PARTICIPANTE_ID = p.id
inner join EMP_PARCELA as pe on pe.idContratoEmprestimo = c.idContratoEmprestimo
where c.dtInicioContrato <= '2014-08-01' and pi.INSTITUIDOR_ID = 1
and c.avaliado is true
and pe.mesCompetencia = '2014-08-01'
and c.deferido is true
and c.dtQuitacao is null
and c.dtExclusao is null
and pe.valorPago is not null
group by c.idContratoEmprestimo
order by p.nome

what is the equelent of sql query in hibernate

In SQL Server i am using this query
select *
from Unit c
ORDER BY CONVERT(INT, LEFT(name, PATINDEX('%[^0-9]%', name + 'z')-1)) desc;
I want this query to use in Hibernate. when I use this in Hibernate I got error
java.lang.IllegalArgumentException: org.hibernate.hql.ast.QuerySyntaxException:unexpected token: LEFT near line 1, column 122
[SELECT c FROM models.entities.UnitEntity c WHERE c.expSetId = :expSetId AND isWaitArea=:isWaitArea ORDER BY CONVERT(INT, LEFT(name, PATINDEX('%[^0-9]%', name + 'z')-1)) asc]

some of that is not in the hibernate dialect, you can change left with substring, convert with cast. and as for patindex i couldn't find the substitution. you either can add pathindex to the constructor of the dialect that you use
registerFunction( "patindex", new StandardSQLFunction("patindex") );
or create patindex() to a stored procedure.
then you can use something like this:
from Unit c order by cast(substring(name, 0, PATINDEX('%[^0-9]%', name + 'z')-1) as integer);
or you can use locate() instead of patindex(), but i think it doesn't support regular expression.

I am pretty sure that you can use SQL query with hibernate as well. When you create your hibernate session, you can use something like
session.createSQLQuery("Your Query Here")
Hope this helps.

java.lang.String cannot be cast HQL

Updated
Error says:
ava.lang.String cannot be cast to com.test.test.classes.TblTaxType
what is happening is when I add the tag select distinct taxtcode error is appearing. But when I removed the select tag like FROM tblTaxType tbl_tax_type WHERE bfnsCode = ? everything is fine. What is the cause? this is my code:
String hql = "SELECT DISTINCT TAXT_CODE FROM tbl_tax_type WHERE BFNS_CODE = ?";
try {
setSession(HibernateUtil.getSession());
#SuppressWarnings("unchecked")
List <TblTaxType> resultList = getSession().createSQLQuery(hql)
.setString(0, bfnsCode)
.list();

Your entity is probably named TblTaxType, not tblTaxType. Case matters.
Side note: don't name sql an HQL query. SQL and HQL are different languages.

Solved it using GROUP BY instead by using DISTINCT.
String hql = "FROM TblTaxType tbl_tax_type WHERE bfnsCode = ? GROUP BY taxtCode";

Your query returns TAXT_CODE, this field is a property of your TblTaxType entity, so you can't cast one property (string) in your main entity. This is the reason of your error.
If you need complete entity you must change your query but DISTINCT is not useful in this case because if you extract complete entity, there's ID field (different for each row). If you want a first element, you can add in your query ORDER BY clause with LIMIT 1 (is MySql).
A solution with GROUP BY works only if you use MySql as DBMS because if you have Sql Server the correct behaviour of field list / group by is: a field in field list must be in GROUP BY cluse or must be in aggregate function.

How can I use MySQL assign operator(:=) in hibernate native query?

I'm using Hibernate. I wrote some native query because I need to use sub select statement.
Query looks like this:
SELECT sub.rownum FROM
(SELECT k.`news_master_id` AS id, #row := #row + 1 AS rownum
FROM keyword_news_list k
JOIN (SELECT #row := 0) r
WHERE k.`keyword_news_id` = :kid
ORDER BY k.`news_master_id` ASC) AS sub
WHERE sub.id = :nid
When I run this query like this:
sessionFactory.getCurrentSession()
.createSQLQuery(query)
.setParameter("kid", kid)
.setParameter("nid", nid)
.uniqueResult();
This exception comes out:
org.hibernate.QueryException: Space is not allowed after parameter prefix ':' ....
This might because of := operator. I found some Hibernate issue about this. This issue is still open. Isn't there any solution for this problem?

Note that HHH-2697 is now fixed for Hibernate 4.1.3 You can now escape with backslash:
SELECT k.`news_master_id` AS id, #row \:= #row + 1 AS rownum
FROM keyword_news_list k
JOIN (SELECT #row \:= 0) r
WHERE k.`keyword_news_id` = :kid
ORDER BY k.`news_master_id` ASC

Another solution for those of us who can't make the jump to Hibernate 4.1.3.
Simply use /*'*/:=/*'*/ inside the query. Hibernate code treats everything between ' as a string (ignores it). MySQL on the other hand will ignore everything inside a blockquote and will evaluate the whole expression to an assignement operator.
I know it's quick and dirty, but it get's the job done without stored procedures, interceptors etc.

you can implement this is a slightly different way.. you need to replace the : operator with something else (say '|' char ) and in your interceptor replace the '|' with the : .
this way hibernate will not try to think the : is a param but will ignore it
For the interceptor logic you can refer to the hibernate manual
This has worked for me using MySQL 5.
remember, this replacing of : must be only done to ':=' and other MySQL specific requirments.. don't try to replace the : for the param-placeholders. (hibernate will not be able to identify the params then)

I prefer to include Spring JDBC and execute the query rather than fight against Hibernate interceptors.

in Hibernate exception on encountering mysql := operator Stanislav gave another option other than interceptor to solve this issue

If you keep your SQL-files away from Java code - try this piece of code. Played a lot to get the right number of escaping slashes:
String sqlPattern = FileUtils.readFile(this.getClass(), /sql/my_query.sql");
sqlPattern = sqlPattern.replaceAll(":=", "\\\\:=");
Query query = entityManager.createNativeQuery(sqlPattern);

I guess there should not be a space after = , the operator should be written as =: (without any spaces)