Japanese GORM - Querying

?????????????  {excerpt:hidden=true} Domain Class Querying {excerpt}

????????????????  {excerpt:hidden=true} Querying with dynamic methods {excerpt}

{excerpt:hidden=true} There are several ways to query for domain class instances, one of them being via Grails dynamic methods, from more details see DomainClass Dynamic Methods:{excerpt}

???????????????????Grails????????????????????????????DomainClass Dynamic Methods??????????

def results = Book.findByTitle("The Stand")
results = Book.findByTitleLike("Harry Pot%")
results = Book.findByReleaseDateBetween( firstDate, secondDate )
results = Book.findByReleaseDateGreaterThan( someDate )
results = Book.findByTitleLikeOrReleaseDateLessThan( "%Something%", someDate )
// find by relationship
results = Book.findAllByAuthor( Author.get(1) )

??????  {excerpt:hidden=true} Querying by example{excerpt}

{excerpt:hidden=true} Just pass an example of the domain object you would like to find to the find() method. {excerpt}

find()???????????????????????? 

def b = Book.find( new Book(title:'The Shining') )

criteria builder??????  {excerpt:hidden=true} Querying with a criteria builder {excerpt}

{excerpt:hidden=true} For more advanced queries or querying across objects graphs you can use Criteria (for a full reference see the section on Builders): {excerpt}

?????????Criteria??????????????????????????????????

def c = Book.createCriteria()
def results = c {
like("author.name", "Stephen%")
between("releaseDate", firstDate, secondDate )
}

HQL?????? {excerpt:hidden=true} Querying with HQL queries {excerpt}

{excerpt:hidden=true} Otherwise, as Grails uses Hibernate internally you can use an HQL query: {excerpt}

?????Grails?Hibernate?HQL?????????????? 

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

 ?????????????????

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