Hibernate - New colums from a joined table [duplicate] - sql

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Hibernate One-To-Many Unidirectional on an existing DB
(4 answers)
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I have a class User object. I am trying to load this object from the Database using Hibernate.
My SQL statement is:
SELECT
users.uid AS uid,
users.deleted AS deleted,
users.username AS username,
users.passwd AS passwd,
users.disabled AS disabled,
users.lockout AS lockout,
users.expires AS expires,
data_firstname.value AS firstname,
data_lastname.value AS lastname
FROM
ac_users as users
LEFT JOIN
ac_userdef_data as data_firstname
ON
users.uid = data_firstname.parentuid AND
data_firstname.fieldname like 'firstname'
LEFT JOIN
ac_userdef_data as data_lastname
ON
users.uid = data_lastname.parentuid AND
data_lastname.fieldname like 'lastname'
WHERE
users.deleted = 0
My mapping for the User class is:
<class name="com.agetor.commons.security.User" table="ac_users">
<id name="uid" column="uid" type="long" >
<generator class="native"/>
</id>
<property name="deleted" column="deleted" />
<property name="username" column="username" />
<property name="password" column="passwd" />
<property name="firstname" column="firstname" />
<property name="lastname" column="lastname" />
<property name="disabled" column="disabled" />
<property name="lockout" column="lockout" />
<property name="expires" column="expires" />
</class>
My problem is that the table ac_users does not have a column 'firstname' or 'lastname'
These columns, only exist in my resultset from the SQL-join statement.
They do also not exist in the ac_userdef_data table. There i have 2 colums: fieldname and value. and 2 rows:
fieldname = 'firstname' with some value in the value column
and another row with
fieldname = 'lastname' with some value in the value column
How do i change my mapping file, so that Hibernate will understand that it needs to load the firstname and lastname column into my firstname and lastname fields on my POJO, while those columns dont actually exist on the referenced ac_users table.?

Answer 1

I now have some working code. The trick was to specify a loading Query for the User class. Hibernate then validates against the return from the Query instead of the Table design.
Class mapping
<class name="com.agetor.commons.security.User" table="ac_users">
<id name="uid" column="uid" type="long" >
<generator class="native"/>
</id>
<property name="deleted" column="deleted" />
<property name="username" column="username" />
<property name="password" column="passwd" />
<property name="firstname" column="firstname" />
<property name="lastname" column="lastname" />
<property name="disabled" column="disabled" />
<property name="lockout" column="lockout" />
<property name="expires" column="expires" />
<loader query-ref="GetAllUsers" />
</class>
My Query declaration
<sql-query name="GetAllUsers">
<return alias="user" class="com.agetor.commons.security.User" />
<![CDATA[
SELECT
users.uid AS uid,
users.deleted AS deleted,
users.username AS username,
users.passwd AS passwd,
users.disabled AS disabled,
users.lockout AS lockout,
users.expires AS expires,
data_firstname.value AS firstname,
data_lastname.value AS lastname
FROM
ac_users as users
LEFT JOIN
ac_userdef_data as data_firstname
ON
users.uid = data_firstname.parentuid AND
data_firstname.fieldname like 'firstname'
LEFT JOIN
ac_userdef_data as data_lastname
ON
users.uid = data_lastname.parentuid AND
data_lastname.fieldname like 'lastname'
WHERE
users.deleted = 0
]]>
</sql-query>
I had to use the line <return alias="user" class="com.agetor.commons.security.User" /> so that the returned collection was typed correctly