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Convert HQL query in the form of "select foo from Foo foo, Bar bar where ..." to Criteria query

In our (ancient) project, we use loads of select queries with HQL on Hibernate version 3.5.6-Final. Because Hibernate will do an auto-commit, because it doesn't know they are select queries, I'm in the process of rewriting all HQL select queries to Hibernate Criteria queries so it won't do in-between commits when we don't want it yet. This is pretty straight-forward in most cases, but I'm currently looking at a query like this, and I'm not sure how to transform it:
Query query = session.createQuery("select municapilityStreet"
+ " from MunicapilityStreet munStreet, Street street"
+ " where munStreet.id = street.MunicapilityStreet.id"
+ " and street.id = :streetId");
query.setParameter(":streetId", streetId);
MunicapilityStreet result = (MunicapilityStreet) query.uniqueResult();
return result;
Here what I have thus far in the process of transforming it:
Criteria criteria = session.createCriteria(MunicapilityStreet.class);
// No idea what to set here to only get the "municapilityStreet" as result
criteria.setProjection(??);
// I'm not sure if this is correct. With a criteria on a single table it would have been simply "Id".
// Both tables have the column-name Id, and I'm not sure how to differentiate between them.
criteria.add(Restrictions.eq("Street.Id", streetId));
MunicapilityStreet result = (MunicapilityStreet) criteria.uniqueResult();
return result;
Maybe I should create a different question for each, but converting the above HQL query to a Criteria has three points I'm not sure about how to do:
How to do a select with multiple tables (the from MunicapilityStreet munStreet, Street street part)?
How to have a projection to only return a single table of the two (the select municapilityStreet part)?
How to have an equal-Restriction on a column name of one table, even though both tables have the same column-name (the and street.id = :streetId part)?

I do oppose the rewrite approach, I hope I'm not impolite doing so.
Hibernate allows to control commits (autocommit is by default off), and what you're experiencing are Entitymanager-flushes, they are auto by default and can be disabled too. And, finally, I think, there is no difference if you're running HQL or criteria queries, same machinery underneath.

Spring JPA Method name for a 2 table query using #Query

EDITTED
Curious... I have a custom Spring JPA query which I'm not sure how to write.
I'm extending PagingAndSortingRepository
The #Query: select * from Table1 tb1 JOIN Table2 tb2 on tb1.id = tb2.tb1_id
where tb2.personId = :personId and tb1.mainId=:mainId and tb2.status in (:statusList)
I'm not sure how to create the method name for this as it keeps giving me an error saying it can't find status in the Table1.
I figured something like:
public Page findByMainIdAndStatusInAndPersonId(#Param("mainId") Integer mainId, ..........); would work but it's telling me it can't find status. Which is understandable since status is in the Table2 object which I'm trying to join on.
**Table1**
id
column1
column2
mainId
List<Table2> table2List
**Table2**
id
table1_id
status
person_id
table 1 and 2 are linked via table2's table_id column. however in the Table1 JPA repository, I need to fetch all of Table1 based on criteria in Table2.
I checked "property expressions" but I'm not catching how to write the jpa method name
Thanks guys :)

After a while of looking around and trying different things... ANSWER:
When you want to query on Table2, you need to add it to the method as:
findBymainIdAndTable2List_StatusInAndTable2List_personId
So essentially add the list name followed by underscore and the column name in that table. If anyone wants to add more, def feel free :D This is how I got it to work

JOIN 2 tables and select specific rows

I use Wordpress table to populate the javafx TableView.
In WP db I have 2 tables wp_posts & wp_postmeta and I need JOIN the table by ID (post_id in wp_postmeta) and select specific rows from wp_postmeta (not all).
For Exampe:
wp_postmeta structure post_id, meta_key, meta_value. In meta_key there is 3 rows - _yoast_wpseo_title, ._yoast_wpseo_metadesc, ._yoast_wpseo_focuskeywords
and I need this rows value from column meta_value.
My code:
ResultSet rs = connection.createStatement().executeQuery(" SELECT wp_postmeta._yoast_wpseo_title, wp_postmeta._yoast_wpseo_metadesc, wp_postmeta._yoast_wpseo_focuskeywords, wp_posts.post_title, wp_posts.post_name FROM wp_postmeta INNER JOIN wp_posts ON wp_posts.ID = wp_postmeta.post_id ");
And of course I receive error that columns _yoast_wpseo_title, _yoast_wpseo_metadesc, _yoast_wpseo_focuskeywords not found because thay are rows.
How I can do this? (I use java9, javafx, mysql jdbc). Or may be I must use PreparedStatement?
Screenshot:

Since you want to filter your query based on the content of the meta_key field, you use a WHERE clause:
SELECT wp_postmeta.meta_key, wp_postmeta.meta_value, wp_posts.post_title
FROM wp_postmeta INNER JOIN wp_posts ON wp_posts.ID = wp_postmeta.post_id
WHERE wp_postmeta.meta_key IN ('_yoast_wpseo_title', '_yoast_wpseo_metadesc', '_yoast_wpseo_focuskeywords')
You are providing a list of the meta keys you want to match. This will give (up to) three rows for each post.
If you want only one row for each post, things get more complicated (and probably aren't worth the trouble). You can use GROUP BY post_id and then study the Aggregate functions.

JPA CriteriaQuery with ListJoin

I'm working with JPA CriteriaBuilder, CriteriaQuery etc. and static metamodels for typesafe queries, like here for example: click.
I have 3 tables: Client, Package, Vegetable.
Every client has 1 or more packages, and those packages contain multiple vegetables.
What I have now:
CriteriaBuilder builder = entityManager.getCriteriaBuilder();
CriteriaQuery<Client> query = builder.createQuery(Client.class);
Root<Client> root = query.from(Client.class);
ListJoin<Package, Vegetable> join = root.join(Client_.packages).join(Package_.vegetables);
TypedQuery<Client> typedQuery = entityManager.createQuery(query);
return typedQuery.getResultList();
The ListJoin I added recently. Point is what Hibernate does: generates the whole select for all fields in Client class from the Client table inner joined with Package and Vegetable, but it doesn't actually selects those fields from joined tables. It gets every package by ID and then every vegetable by ID, thus doing n+1 selects.
Without the ListJoin it doesn't inner join those tables, but I'm working on it right now so I added those joins. Now I want to select all the fields from those classes so I get whole object hierarchy with 1 select. I tried doing something with projections like in the link I gave in Projecting the result chaper, but I have no idea how to connect that with ListJoin.
Is that even possible in this situation? When I run this query on database (with manually added all the fields from joined tables) it works fine, but would Hibernate handle that? And if so - how to project the result so it selects all the fields from 3 tables joined together and constructs whole object hierarchy, all with 1 select?
//Edit: managed to retrieve all packages with a single query, but going further raises exception:
Root<Client> root = query.from(Root.class);
ListJoin<Client, Package> join = root.join(Client_.packages);
ListJoin<Package, Vegetable> secondJoin = join.join(Package_.vegetables);
root.fetch(Client_.packages);
Naturally, I tried to add: join.fetch(Package_.vegetables); but it raises the org.hibernate.QueryException: query specified join fetching, but the owner of the fetched association was not present in the select list, no idea what is that.
As to the latest comment: gonna try that now.
//Edit2: I added 2 fetches (couldn't cast them to Join like in that answer, compiler errors):
Fetch<Client, Package> join = root.fetch(Client_.packages);
Fetch<Package, Vegetable> secondJoin = join.fetch(Package_.vegetables);
It raises org.hibernate.loader.MultipleBagFetchException: cannot simultaneously fetch multiple bags, known error I guess so at least got something to search for.
//Edit3: Changed it both to Sets and it works, thanks, couldn't have done it without the Fetch instead of Join suggestion, seems kinda unintuitive to me.

Convert Postgresql query to Hibernate

In my Java Web application I use Postgresql and some data tables are filled automatically in server. In the database I have a STATUS table like below:
I want to select the data related to a vehicle between selected dates and where the vehicle stayed connected. Simply I want to select the data which are green in the above table which means I exactly want the data when firstly io1=true and the data when io1=false after the last io1=true. I have postgresql query statement which exactly gives me the desired data; however, I have to convert it to HQL because of my application logic.
working postgresql query:
WITH cte AS
( SELECT iostatusid, mtstrackid, io1,io2,io3, gpsdate,
(io1 <> LAG(io1) OVER (PARTITION BY mtstrackid
ORDER BY gpsdate)
) AS status_changed
FROM iostatus
WHERE mtstrackid = 'redcar' AND gpsdate between '2014-02-28 00:00:00' and '2014-02-28 23:59:59'
)
SELECT iostatusId, mtstrackid, io1, io2, io3,gpsdate
FROM cte
WHERE status_changed
OR io1 AND status_changed IS NULL
ORDER BY gpsdate ;
How should I convert the above query to HQL or how could I retrieve the desired data with HQL?

The goal of hibernate is mapping database entities to java objects. This kind of complex queries are not entities themselves. This is against the spirit of hibernate.
If this query generates an entity in your application logic, I recommend putting the results into a table and applying Hibernate queries to that table.
If this query generates some kind of aggregation or summary, there are two possible ways:
One way is you compute this aggregation/summary in your application after retrieving entities from iostatus table with hibernate.
If this query has nothing to do with your application logic then you can use Native SQL interface of Hibernate and execute the query directly. (You can even use JPA if you are willing to manipulate two database connections.)
If you absolutely need to convert it to HQL, you need to eliminate the partition function. If the order of iostatusId is identical to the order of gpsdate, you can do it similar to
SELECT i2.*
FROM iostatus i1
INNER JOIN iostatus i2 ON i1.iostatusId = i2.iostatusId - 1
AND i1.io1 <> i2.io1
AND i1.mstrackid = i2.mstrackid
WHERE i2.mtstrackid = 'redcar' AND
i2.gpsdate between '2014-02-28 00:00:00' and '2014-02-28 23:59:59'
If gpsdate is no way related to iostatusId then you need something like
SELECT i2.*
FROM iostatus i1
INNER JOIN iostatus i2 ON i1.gpsdate < i2.gpsdate
AND i1.io1 <> i2.io1
AND i1.mstrackid = i2.mstrackid
WHERE i2.mtstrackid = 'redcar' AND
i2.gpsdate between '2014-02-28 00:00:00' and '2014-02-28 23:59:59' AND
NOT EXISTS (SELECT * FROM iostatus i3
WHERE i3.gpsdate > i1.gpsdate AND
i2.gpsdate > i3.gpsdate AND
i3.io1 = i1.io1 AND
i1.mstrackid = i3.mstrackid)
I guess both of the queries can be converted to HQL, but I'm not positively sure.
By the way I must warn you that, these methods might not perform better then finding the changes in your application, because they involve joining the table onto itself, which is an expensive operation; and the second query involves a nested query after the join, which is also quite expensive.