As well as associations between different domain classes, GORM also supports mapping of basic collection types. For example, the following class creates a nicknames association that is a Set of String instances:

class Person {
    static hasMany = [nicknames:String]
}

GORM will map an association like the above using a join table. You can alter various aspects of how the join table is mapped using the joinTable argument:

class Person {
    static hasMany = [nicknames:String]

static mapping = { hasMany joinTable: [name: 'bunch_o_nicknames', key: 'person_id', column: 'nickname', type: "text"] } }

The example above will map to a table that looks like the following:

bunch_o_nicknames Table

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| person_id         |     nickname          |
---------------------------------------------
|   1               |      Fred             |
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