根据ER-diagram创建grails域

Question

我有急症室图。我试着像grails域那样描述它，但在启动项目之后，只有部分表存在（创建）。我找不到我在哪个地方犯了错。

class Song {

    static hasMany = [audios: Audio, tags: Tag]

    BigInteger id

    String title
    String chorus
    Boolean chorusRepeat
    Date created
    Date updated

    static constraints = {
        tags joinTable:[name:'song_tag', key:'song_id']
    }
}


class Tag {

    static belongsTo =  Song
    static hasMany = [songs: Song]

    BigInteger id
    String name

    static constraints = {
        songs joinTable:[name: 'song_tag', key: 'tag_id']
    }
}

class Couplet {

    static belongsTo = Song

    BigInteger id
    String text
    Song song

    static constraints = {
    }
}

class Audio {

    static belongsTo = Song

    BigInteger id

    String audio
    String type
    Date created
    Date updated
    Song song

    static constraints = {
    }
}

控制台输出

2015-02-01 14:20:36,007[localhost-startStop-1]错误hbm2ddl.schemaexport-hhh000389:失败：创建表对（id decimal（19,2）不为空,版本bigint不为空,song_id decimal（19,2）不为空,text varchar(255)不为空,主键(id))Engine=InnoDB错误2015-02-01 14:20:36,007[localhost-startStop-1]错误hbm2ddl.schemaexport-列“id”的列说明符不正确

谢谢你

Answer 1

有两件事必须改变

1）

 static constraints = {
    songs joinTable:[name: 'song_tag', key: 'tag_id']
}

它应该在映射闭包中，而不是在约束闭包中

static mapping = {  songs joinTable:[name: 'song_tag', key: 'tag_id']}

2）只需从域中删除id字段，GORM就会自动创建id字段。