Hibernate - (HQL and JPQL) Insert statements

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Insert statements

HQL adds the ability to define INSERT statements as well.

There is no JPQL equivalent to HQL-style INSERT statements.

HQL INSERT statement is:

insert_statement ::=
    insert_clause select_statement

 insert_clause ::=
    INSERT INTO entity_name (attribute_list)

 attribute_list ::=
    state_field[, state_field ]*

 The attribute_list is analogous to the column specification in the SQL INSERT statement. For entities involved in mapped inheritance, only attributes directly defined on the named entity can be used in the attribute_list. Superclass properties are not allowed and subclass properties do not make sense. In other words, INSERT statements are inherently non-polymorphic.

select_statement can be any valid HQL select query, with the caveat that the return types must match the types expected by the insert. Currently, this is checked during query compilation rather than allowing the check to relegate to the database. This may cause problems between Hibernate Types which are equivalent as opposed to equal. For example, this might cause lead to issues with mismatches between an attribute mapped as a org.hibernate.type.DateType and an attribute defined as a org.hibernate.type.TimestampType, even though the database might not make a distinction or might be able to handle the conversion.

For the id attribute, the insert statement gives you two options. You can either explicitly specify the id property in the attribute_list, in which case its value is taken from the corresponding select expression, or omit it from the attribute_list in which case a generated value is used. This latter option is only available when using id generators that operate "in the database"; attempting to use this option with any "in memory" type generators will cause an exception during parsing.

For optimistic locking attributes, the insert statement again gives you two options. You can either specify the attribute in the attribute_list in which case its value is taken from the corresponding select expressions or omit it from the attribute_list in which case the seed value defined by the corresponding org.hibernate.type.VersionType is used.

INSERT query statements

int insertedEntities = session.createQuery(
"insert into Partner (id, name) " +
"select p.id, p.name " +
"from Person p ")
.executeUpdate();

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