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How to use FIND_IN_SET in jpa

How can I use find_in_set in jpa?
I need to achieve like this
SQL - select * from teacher where find_in_set("5", deptIds) and id = 101
where deptIds have comma separated ids (I know it's bad idea but legacy.)
To do so I had been tried using Criteria but not found any Restrictions that can fulfill find_in_set.
Note - need possible solution with Criteria and Restrictions

criteriaBuilder.function("find_in_set", Boolean.class,
criteriaBuilder.literal(s),
root.get("field"))

Here is an example:
Here is java code snippet.
list.add(cb.greaterThan(cb.function("FIND_IN_SET", Integer.class,
cb.literal(val.toString()), root.get(attributeName)), 0));

select t from Teacher t where find_in_set("5", t.deptIds) = 0 and t.id = 101

How to use multiple values in WHERE using JPA CriteriaBuilder

I have an example MyTable with 3 columns - id, common_id, creation_date, where common_id groups entries.
Now I would like to select using CriteriaBuilder all newest entries from each group (that is for each common_id get me latest creation_date).
In SQL the query would look like this:
select * from MyTable where (common_id, creation_date) in (select common_id, max(creation_date) from MyTable group by common_id)
Now I have tried to create the where predicate by writing something like (cb is CriteriaBuilder, root is a Root):
cb.array(root.get('common_id'), cb.max(root.get('creation_date')))
.in(
query.subquery(MyTable.class)
.select(cb.array(root.get('common_id'), cb.max(root.get('creation_date'))))
.groupBy(root.get('common_id')))
But unfortunately cb.array is not an Expression (it's a CompoundSelect), so I cannot use .in() on it.
Thanks for pointers!

could you create it using JPQL? As far that I know, that is not possible.
I looked at the Spect (4.6.16 Subqueries) and it talk about "simples select expression":
simple_select_clause ::= SELECT [DISTINCT] simple_select_expression
I believe that only one return is possible, if you look at the examples there you will not find anything like it.
You will need to use NativeQuery for it.

How to use CONCAT_WS() in Hibernate HQL

To combine multiple columns as one,
I found one answer
SELECT id,CONCAT_WS(',', field_1, field_2, field_3, field_4) list
FROM `table`;
This query working fine in SQL but it gives me error in HQL:
Error is .
(java.lang.IllegalStateException: No data type for node: org.hibernate.hql.internal.ast.tree.MethodNode )
please help me to find out what wrong i did, help me to know how to use CONCAT_WS() IN HQL
below how i written my HQL query
SELECT C1._URI,C1.HEALTH_FACILITY,C1.DISTRICT,CONCAT_WS(',', C1.BLOCKS_OF_BHUBRI, C1.BLOCKS_OF_GOLAGHAT, C1.BLOCKS_OF_HAILAKANDI) as Block_name
FROM GapAnalysisWashInHealthFacilitiesCore C1
any help will appreciate

CONCAT_WS is a function specific to mySql. HQL is a generic language and not aware of native SQL functions and syntax. If you really need the function, then you should use Hibernate's API for native SQL.
Session session = ...;
Query query = session.createSQLQuery("
SELECT id,CONCAT_WS(',', field_1, field_2, field_3, field_4) Block_name FROM `table`");
List result = query.list();
Then you may like to have a look at Result Transformers to get result as list of GapAnalysisWashInHealthFacilitiesCore objects.

avoiding multiple selects when using kew word "new" in hql

I have the following code in java.
List<UserHelper> users=List<UserHelper>)session.getNamedQuery("PkUser.loadHelperUsers").list();,
I think it does not matter what the "UserHelper" class is that's why I do not write it, not to overload my question. This is my namedQuery mentioned above.
#NamedQuery(name = "PkUser.loadHelperUsers", query = "SELECT new ge.tec.pto.ext.helpers.UserHelper(u) from PkUser u order by u.pkUserId desc"),
The problem is that the hql selects too many rows, I think the same number of rows that is in database in pk_user table.If anyone knows how to fix this please inform me. It will be very nice if the solution will not require to alter my "NamedQuery", It will be graet if I will have to change only my Query creation, But any solutions will be helpful, Thank you

Multiple selects when using Key word “`new`” in `hql`
There is no problem with your code and with NEW keyword .
Your query will return all the Rows in the UserHelper related Table
You should use a WHERE clause to get the required rows .
EX :
query = "SELECT new ge.tec.pto.ext.helpers.UserHelper(u) from PkUser u where username=:passedparamer order by u.pkUserId desc"

Select records which doesn't have specific records in joined table

Hi I'm trying to select records from one table which doesn't have records in connected many-to-many table with specific values.
I will explain on sample tables:
documentation:
id_documentation
irrelevant_data
user:
id_user
irrelevant_data
documentation_user:
id_documentation
id_user
role
What I want to achieve is to select every single documentation which doesn't have user in specific role. Any ideas?
The main problem is that I'm using java's CriteriaBuilder to create query so using subqueries is impossible (I think).

You can add restrictions on your left join using: createAlias(java.lang.String, java.lang.String, int, org.hibernate.criterion.Criterion) method, see API.
Check this answer for an example on how to use the left join with a criteria.

Main problem does not exist - Criteria API do have SubQuery. Query itself selects instances of User and uses not in construct to limit results based to subquery. Subquery selects all users that are connected to document with specific role via DocumentationUser.

Try something like this (code not tested):
CriteriaQuery<Documentation> cq = cb.createQuery(Documentation.class);
Root<Documentation> u = cq.from(Documentation.class);
Subquery<Integer> sq = cq.subquery(Integer.class);
Root<User> su = sq.from(User.class);
sq.select(su.get("id_user"));
Join<User, DocumentationUser> du = su.join("documentationUserCollection");
sq.where(cb.equals(du.get("role"), "mySpecificRole"));
cq.where(cb.not(cb.in(u.get("id_user")).value(sq)));
See also this useful answer on SO.