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6.4.5 Hibernate Query Language (HQL) - Reference Documentation

Authors: Graeme Rocher, Peter Ledbrook, Marc Palmer, Jeff Brown, Luke Daley, Burt Beckwith, Lari Hotari

Version: 2.3.8

6.4.5 Hibernate Query Language (HQL)

GORM classes also support Hibernate's query language HQL, a very complete reference for which can be found in the Hibernate documentation of the Hibernate documentation.

GORM provides a number of methods that work with HQL including find, findAll and executeQuery. An example of a query can be seen below:

def results =
      Book.findAll("from Book as b where b.title like 'Lord of the%'")

Positional and Named Parameters

In this case the value passed to the query is hard coded, however you can equally use positional parameters:

def results =
      Book.findAll("from Book as b where b.title like ?", ["The Shi%"])

def author = Author.findByName("Stephen King")
def books = Book.findAll("from Book as book where book.author = ?",
                         [author])

Or even named parameters:

def results =
      Book.findAll("from Book as b " +
                   "where b.title like :search or b.author like :search",
                   [search: "The Shi%"])

def author = Author.findByName("Stephen King")
def books = Book.findAll("from Book as book where book.author = :author",
                         [author: author])

Multiline Queries

Use the line continuation character to separate the query across multiple lines:

def results = Book.findAll("\
from Book as b, \
     Author as a \
where b.author = a and a.surname = ?", ['Smith'])

Triple-quoted Groovy multiline Strings will NOT work with HQL queries.

Pagination and Sorting

You can also perform pagination and sorting whilst using HQL queries. To do so simply specify the pagination options as a Map at the end of the method call and include an "ORDER BY" clause in the HQL:

def results =
      Book.findAll("from Book as b where " +
                   "b.title like 'Lord of the%' " +
                   "order by b.title asc",
                   [max: 10, offset: 20])