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How to use a 'Hibernate Types' library type in a single native query that selects Postgres arrays?

I have a query that returns a Postgres array of UUIDs:
SELECT e.id, e.date,
ARRAY
(
SELECT cs.api_id FROM event_condition_set ecs
JOIN condition_set cs on cs.id = ecs.condition_set_id
WHERE ecs.event_id = e.id
) AS condition_set_ids,
...
And then create and run this query as a native query: Query query = entityManager.createNativeQuery(queryString);
Since Hibernate can normally not deal with these Postgres arrays, I use Vlad's Hibernate Types library.
However, currently I need to register this UUIDArrayType globally in my application:
public class PostgreSQL95CustomDialect extends PostgreSQL95Dialect {
public PostgreSQL95CustomDialect() {
super();
this.registerHibernateType(Types.ARRAY, UUIDArrayType.class.getName());
}
}
Aside from the fact this is a bit ugly, it also leaves no room for other types of arrays.
(Note I also tried registering a generic ListArrayType but this throws a NullPointerException during execution of the query.)
I have also tried registering it as a scalar type:
query.unwrap(org.hibernate.query.NativeQuery.class)
.addScalar("condition_set_ids", UUIDArrayType.INSTANCE);
But this makes the entire query only return a single UUID, which is very strange and seems bugged.
Is there a way to ONLY use this UUIDArrayType specifically in this query?
(Please don't suggest using array_agg because the performance is terrible for this case)

you can call native queries using custom Hibernate types as follows:
String myJsonbData = ...;
String[] myStringArr = ...;
final String queryStr = "select your_function(?, ?, ...)"; // ? for each param
entityManager
.createNativeQuery(queryStr)
.setParameter(1, new TypedParameterValue(JsonBinaryType.INSTANCE, myJsonbData))
.setParameter(2, new TypedParameterValue(StringArrayType.INSTANCE, myStringArr));
This is just an example, but as a rule of thumb, you need to instantiate a new TypedParameterValue.

Answering my own question here. After waiting for a while and updating to the most recent library version (I'm on 2.19.2 right now) I don't have any issues anymore with the scalar types registration as I mentioned in my question, i.e.:
query.unwrap(org.hibernate.query.NativeQuery.class)
.addScalar("condition_set_ids", UUIDArrayType.INSTANCE);
So it appears to just have been a bug and I can now avoid the global registration in favor of using scalars.

Convert Integer to String in Spring Data JPA Query

I need to optimize a query that iterates over several objects and I wanted Spring Data to let the database handle it. I want to end up with a HashMap<String,String> that looks like
2134_9877, 9877
2134_2344, 2344
3298_9437, 9437
The SQL would be select convert(varchar,b.id)+'_'+convert(varchar,a.id)',a.id from t1 a join t2 b on a.jc = b.jc
So far, I've got Whatever-QL in the repository that looks like:
#Query("SELECT new map (a.bkey, a.akey) FROM mergeTable a WHERE a.discr= ?1")
The problem is, bkey is not unique, it is only unique when paired with akey and the monstrosity that I have to feed it to wants them combined with an underscore: 2345_2177.
I have tried a.bkey.toString and ''+a.bkey and new String(a.bkey) and just string(a.bkey) (that last gives a new exception but still doesn't work) but Spring doesn't like any of these. I can find no questions asking this and it seems I cannot use SQLServer's convert() function as this ain't SQL.
How can I concatenate the Integers as Strings with an underscore in this #Query?
PS: Using the native query that's been debugged in SQLServer throws some weird alias exception in Hibernate so I think 'going native' is predetermined to be a dead end.

If I have understood it right, the 'Whatever-QL' is called JPQL, and the operator CONCAT can be used. Only the use of it, as it accepts two or more parameters depends on the JPA version you are running.
Here is the answer.
JPA concat operator

You could add a getter to your entity like this:
public String getCombinedKey(){
return a.akey + "_" + a.bkey;
}
The advantage is you could handle here null's and other things if you want and it's more reusable in case you need this in another place. If you do it just in the repository you will have to copy it everytime.
Your query would then be:
#Query("SELECT new map (a.combinedKey, a.akey) FROM mergeTable a WHERE a.discr= ?1")

org.hibernate.NonUniqueResultException: query did not return a unique result: 2?

I have below code in my DAO:
String sql = "SELECT COUNT(*) FROM CustomerData " +
"WHERE custId = :custId AND deptId = :deptId";
Query query = session.createQuery(sql);
query.setParameter("custId", custId);
query.setParameter("deptId", deptId);
long count = (long) query.uniqueResult(); // ERROR THROWN HERE
Hibernate throws below exception at the marked line:
org.hibernate.NonUniqueResultException: query did not return a unique result:
I am not sure whats happening as count(*) will always return only one row.
Also when i run this query on db directly, it return result as 1. So whats the issue?

It seems like your query returns more than one result check the database. In documentation of query.uniqueResult() you can read:
Throws: org.hibernate.NonUniqueResultException - if there is more
than one matching result
If you want to avoid this error and still use unique result request, you can use this kind of workaround query.setMaxResults(1).uniqueResult();

Hibernate
Optional findTopByClientIdAndStatusOrderByCreateTimeDesc(Integer clientId, Integer status);
"findTop"!! The only one result!

I don't think other answers explained the key part: why "COUNT(*)" returns more than one result?
I just encountered the same issue today, and what I found out is that if you have another class extending the target mapped class (here "CustomerData"), Hibernate will do this magic.
Hope this will save some time for other unfortunate guys.

Generally This exception is thrown from Oracle when query result (which is stored in an Object in your case), can not be cast to the desired object.
for example when result is a
List<T>
and you're putting the result into a single T object.
In case of casting to long error, besides it is recommended to use wrapper classes so that all of your columns act the same, I guess a problem in transaction or query itself would cause this issue.

It means that the query you wrote returns more than one element(result) while your code expects a single result.

Received this error while doing otherwise correct hibernate queries. The issue was that when having a class extend another hibernate was counting both. This error can be "fixed" by adding a method to your repository class.
By overriding the class count you can manually determine the way this is counted.
#Override
public Integer count(Page<MyObject> page) {
// manual counting method here
}

I was using JPQL and wanted to return Map. In my case, the reason was that I wanted to get Map<String, String>, but had to expect List<Map<String, String>> :)

Check your table, where one entity occurring multiple time's.
I had the same error, with this data :
id
amount
clientid
createdate
expiredate
428
100
427
19/11/2021
19/12/2021
464
100
459
22/11/2021
22/12/2021
464
100
459
22/11/2021
22/12/2021
You see here clientid occurring two times with 464.
I solved it by deleting one row :
id
amount
clientid
createdate
expiredate
428
100
427
19/11/2021
19/12/2021
464
100
459
22/11/2021
22/12/2021

I have found the core of the problem:
result of SELECT COUNT(*) can be a list, if there is a GROUP BY in the query,
and sometimes Hibernate rewrite your HQL and put a GROUP BY into it, just for fun.

Basically your query returns more than one result set.
In API Docs uniqueResult() method says that
Convenience method to return a single instance that matches
the query, or null if the query returns no results
uniqueResult() method yield only single resultset

Could this exception be thrown during an unfinished transaction, where your application is attempting to create an entity with a duplicate field to the identifier you are using to try find a single entity?
In this case the new (duplicate) entity will not be visible in the database as the transaction won't have, and will never be committed to the db. The exception will still be thrown however.

Thought this might help to someone, it happens because "When the number of data queries is greater than 1".reference

As what Ian Wang said, I suspect you are using a repository from spring. And a few days ago you just copy past a class and forgot to delete it when it is finally unused. Check that repository, and see if there is multiple same class of table you use. The count is not the count of rows, but the count of the table problem.

This means that orm technology is not preprogrammed to give you which results you are looking for because there are too many of the same results in the database. for example If there is more than one same value in my database and I want to get it back, you will encounter the error you get with the select query.

For me the error is caused by
spring.jpa.hibernate.ddl-auto=update
in application.properties file replacing it with
spring.jpa.hibernate.ddl-auto=create solved the issue, but it still depends on your needs to decide which configuration you need in your project, for more insights on the topic check this.

First you must test the query list size; here a example:
long count;
if (query.list().size() > 0)
count=(long) criteria.list().get(0);
else
count=0;
return count;

Passing String value to SQL bigint column

Given following Statment:
String query = "Select * from T_spareParts where SparePartPK IN (? )"
In my BackBean (JSF 2) I first iterate through all cars in table and build a String of all the cars currently selected (by picking each cars ID as primary key) so the final String before being passed to SQL could look like:
String finalString = " '1','2','3','4'";
And then :
this.prepareStatement= this.connection.prepareStatement(query);
this.prepareStatement.setString(1,finalString);
this.prepareStatement.executeQuery();
Exception thrown is:
Error converting data type nvarchar to bigint.
Now my understanding is that exception is due to SparePartPK is type bigint and we're passing a String .
But in SQL Server (2008) i can do :
Select * from T_spareParts where SparePartPK IN ('1','2','3','4')"
which returns results as expected. Why am i getting the exception and how can i correct the issue? (also feel free to comment if this isn't the best approach)
Update:
I've also tried to produce the finalString without single quotes which causes the same exception to be thrown :
String finalString = " 1,2,3,4";

You should put the numbers into an array (not a string), and use preparedStatement.setArray()

Thanks for the suggestions. Though as an alternative I created a StoredProcedure where it takes one parameter and inside the StoredProcedure i run the above Query in question formulating the IN section using the passed parameter .
So all above code still applies, The parameter passed to the storeDProcedure is one String separated by , without the single quotes.
Might not be the optimum answer but works quit well :) .

JAVA: NamedQuery String problem

Hello guys I am having some problems with exact matches while doing a NamedQuery.
I am currently using something like this:
#NamedQuery(name = MyClass.GET_ENTRY_BY_NAME, query = "select e from Entry e where e.name =:"+ Entry.NAME )
...
Query query = em.createNamedQuery(MyClass.GET_ENTRY_BY_NAME);
query.setParameter(Entry.NAME, myEntry.getName());
It works for most cases, however I noticed that in case the user pass the file name with an space at the end, the namedQuery ignores that character. For example:
Query query = em.createNamedQuery(MyClass.GET_ENTRY_BY_NAME);
query.setParameter(Entry.NAME, myEntry.getName()+ " ");
Will return the same result as the query before. Bypassing my 'valid entry' validation. In other words I'd like the query to return no entry at all and treat the error later on.
One workaround I could think of, is to put single quotes surrounding my parameter in the namedQuery, like this:
#NamedQuery(name = MyClass.GET_ENTRY_BY_NAME, query = "select e from entry e where e.name =':"+ Entry.NAME "'")
However it will trash my code in case the String contains single quotes in it...
Any ideas guys?

I guess this happens because your database field is declared as CHAR(...), and therefore stored values are padded with whitespaces which are not taken into account by = operation.
So, you may either declare your database field as VARCHAR(...) or use a built-in trim function:
query = "select e from Entry e where trim(trailing from e.name) =:"+ Entry.NAME

I did some research in JPA and found out that it does some automatic trimming for CHARs, I am not sure if this behaves the same with Strings, but since it is happening to me... I believe so. The only way to bypass it is by setting some attribute within the session DatabaseLogin object (see http://www.eclipse.org/eclipselink/api/1.1/org/eclipse/persistence/sessions/DatabaseLogin.html#setShouldTrimStrings) .
Well I didn't want to be messing up with the session properties so I decided to make some sort of check and throwing the same exception as the NoResultException catch does in my code.
I basically took the result from the database and compared the field with the String I used:
query.setParameter(Entry.NAME, myEntry.getName());
...
if(!StringUtils.equals(result.getName(), myEntry.getName()){
do a cool throw just like NoResultException Catch
}
I also had to include the Trim function axtavt! This is just to make sure that if the database has a column with trailing spaces and it matches the parameter given by the user, it will be included as a valid answer. For example:
Database entry: Name = "Flavio " - Trimmed with Function = "Flavio".
Parameter passed: Name = "Flavio " - Trimmed by JPA automatic function = "Flavio".
If it isnt trimmed at all it will just Compare "Flavio " with "Flavio", returning NoResult when it was supposed to return that Entry.
Nasty workaround, but as long as there is no other way to stop the auto-trimming we will have to just make use of this sort of things.
Thanks for all the other answers!!