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== find



=== Purpose


Finds the first matching result for the given query or `null` if no instance is found


=== Examples


[source,groovy]
----
// Dan brown's first book
Book.find("from Book as b where b.author='Dan Brown'")

// with a positional parameter
Book.find("from Book as b where b.author=?", ['Dan Brown'])

// with a named parameter
Book.find("from Book as b where b.author=:author", [author: 'Dan Brown'])

// use the query cache
Book.find("from Book as b where b.author='Dan Brown'", [cache: true])
Book.find("from Book as b where b.author=:author",
          [author: 'Dan Brown'],
          [cache: true])

// query by example
def example = new Book(author: "Dan Brown")
Book.find(example)

// Using where criteria (since Grails 2.0)
Person p = Person.find { firstName == "Bart" }
----


=== Description


The `find` method allows querying with Hibernate's query language  link:{hibernate5GuideFromRef}index.html#hql[HQL] and querying by example. The basic syntax is:

[source,groovy]
----
Book.find(String query)
Book.find(String query, Collection positionalParams)
Book.find(String query, Collection positionalParams, Map queryParams)
Book.find(String query, Map namedParams)
Book.find(String query, Map namedParams, Map queryParams)
Book.find(Book example)
Book.find(Closure whereCriteria)
----

Parameters:

* `query` - An HQL query
* `positionalParams` - A `List` of parameters for a positional parametrized HQL query
* `namedParams` - A `Map` of named parameters a HQL query
* `queryParams` - A `Map` of query parameters. Currently, only `cache` is supported
* `example` - An instance of the domain class for query by example
