Question

I have a Grails 1.3.7 domain class that is declared like this:

class Document {
    String url

    Map metadata = new HashMap()

    static constraints = {
        url(nullable:false, blank: false, maxSize: 2048)
        metadata()
    }
}

The schema that is generated looks like this:

+-------------+--------------+------+-----+---------+----------------+
| Field       | Type         | Null | Key | Default | Extra          |
+-------------+--------------+------+-----+---------+----------------+
| id          | bigint(20)   | NO   | PRI | NULL    | auto_increment |
| url         | longtext     | NO   |     | NULL    |                |
+-------------+--------------+------+-----+---------+----------------+

+--------------+--------------+------+-----+---------+-------+
| Field        | Type         | Null | Key | Default | Extra |
+--------------+--------------+------+-----+---------+-------+
| metadata     | bigint(20)   | YES  |     | NULL    |       |
| metadata_idx | varchar(255) | YES  |     | NULL    |       |
| metadata_elt | varchar(255) | NO   |     | NULL    |       |
+--------------+--------------+------+-----+---------+-------+

I am wondering how I can specify different types (specifically, different size) for the document_metadata table. I would like to be able to store strings longer than 255 characters. I could not find any relevant documentation online, possibly because I couldn’t come up with any good keywords. Map and Collection are pretty generic terms!

Thanks,

Gene

Answer 1

The only way you are going to be able to influence the DDL for your “metadata” is to make it a concrete domain class. Using HashMap isn’t going to give you the ability to do so.