discriminator
目的 Purpose
Customizes the discriminator column used in table-per-subclass inheritance mapping.使用例 Examples
class Content {
…
}class PodCast extends Content { … static mapping = { discriminator "audio" } }
詳細 Description
Usage:
使用方法: discriminator(string/map)Usage:
discriminator(string/map)引数: Arguments:
column(optional) - The column name to store the discriminatorvalue- The value to use for the discriminatorformula(optional) - an SQL expression that is executed to evaluate the type of class. Use this orcolumnbut not bothtype(optional defaults to string) - the Hibernate type, used for the where clause condition to know if it needs to wrap it with '
discriminator method to customize what's stored:class Content {
…
}class PodCast extends Content { … static mapping = { discriminator "audio" } }
class Content {
…
static mapping = {
discriminator column: "content_type"
}
}class PodCast extends Content { … static mapping = { discriminator value: "audio" } }
class Content {
…
static mapping = {
discriminator value: "1", type: "integer",
formula: "case when CLASS_TYPE in ('a', 'b', 'c') then 0 else 1 end",
}
}class PodCast extends Content { … static mapping = { discriminator value: "0" } }