Grails查找具有多对多关系的领域对象，并以列表作为参数

Question

I have a simple class Song, to which I can attribute some tags :

class Song {
    String title
    static hasMany = [tags:Tag]
}

Then, i would like to be able to find all songs having a given list of tags, for example this would look like :

List<Song> results = Song.findAll("where tags contains ?", [myTagList]);

For example, if I have :

a Song S1 with tags T1
a Song S2 with tags T1 T2 T3
a Song S3 with tags T1 T3
a Song S4 with tags T1 T2 T3 T4

And I execute my query with myTagList containing T1, T2, T3 , then the call will return S2 and S4 .

Is there any efficient way to perform this ?

Answer 1

It should be possible to use criteria with an "in" query:

Song.createCriteria().list{
    "in"("tags",myTagList)
}

Answer 2

那动态取景器呢？

List<Song> results = Song.findAllByTagsInList(myTagList);