How do I create a query connecting two tables using Hibernate?

@alyce 

To create a query connecting two tables using Hibernate, you can use the Hibernate Query Language (HQL). HQL is a powerful and flexible query language that allows you to write queries in a more readable and understandable form.

Here's an example of how to create a query connecting two tables using HQL:

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String hql = "SELECT t1.column1, t2.column2 FROM Table1 t1, Table2 t2 WHERE t1.id = t2.id";
Query query = session.createQuery(hql);
List results = query.list();

In this example, the query retrieves the value of column1 from Table1 and column2 from Table2, and combines the two tables based on a matching id column. The session.createQuery method creates the query and the query.list method executes it, returning the results as a list of objects.

Note that this is just a simple example, and you can write much more complex queries using HQL, including joins, subqueries, and aggregation functions.

@alyce 

Additionally, you can also use Hibernate's Criteria API to create a query connecting two tables. The Criteria API provides a type-safe and object-oriented approach to query generation. Here's an example of how to create a query connecting two tables using the Criteria API:

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CriteriaBuilder builder = session.getCriteriaBuilder(); CriteriaQuery query = builder.createQuery(Type.class); Root table1Root = query.from(Table1.class); Root table2Root = query.from(Table2.class); query.select(builder.construct(Type.class, table1Root.get("column1"), table2Root.get("column2"))) .where(builder.equal(table1Root.get("id"), table2Root.get("id"))); List results = session.createQuery(query).getResultList();

In this example, the query constructs a new object of Type using the column1 from Table1 and column2 from Table2. It then joins the two tables based on a matching id column using the equal method of the CriteriaBuilder class.The session.createQuery method creates the query, and the getResultList method executes it, returning the results as a list of objects. Note that you will need to replace the Type class name with the appropriate object type that matches the selected columns from both tables.