== Primary Key Management ==

Transfer has several ways of handling primary keys:

=== Database specific ===

==== Microsoft SQL Server ====

Retrieve the last created Identity value for the table, e.g.

<code><pre>
<id name="userid" type="numeric" />
</pre></code>

==== mySQL ====

Retrieve the last created auto increment value for the table, e.g.

<code><pre>
<id name="userid" type="numeric" />
</pre>
</code>

==== PostGreSQL ====

Retrieve the last sequence value mapped to the table, e.g.

<code><pre>
<object name="User" sequence="user_sequence">
<id name="idbasic" type="numeric" />
 ... 
</pre></code>

==== Oracle ====

Retrieve the last sequence value mapped to the table, e.g.

<code><pre>
<object name="User" sequence="user_sequence">
<id name="idbasic" type="numeric" />
 ...
</pre></code>

=== Generic ===

Transfer also has the capabily to generate for you:

==== Numeric Primary Keys ====

Transfer can generate unique numeric keys per table, by setting generate='true' when the type is 'numeric' e.g.

<code><pre>
<id name="userid" type="numeric" generate="true" />
</pre></code>

==== UUID Primary Keys ====

Transfer can generate UUID keys, by setting generate='true' when the type is 'UUID' e.g.

<code><pre>
<id name="userid" type="UUID" generate="true" />
</pre></code>

==== GUID Primary Keys ====

Transfer can generate GUID keys, by setting generate='true' when the type is 'GUID' e.g.

<code><pre>
<id name="userid" type="GUID" generate="true" />
</pre></code>

=== Manual ===

Lastly, this can all be manually overwritten simply by setting the primary key value via the set() method prior to the TransferObject being created in the database, e.g.

<code><pre>
user = getTransfer().new("User");<br /> user.setUserID(1);
getTransfer().save(user); 
</pre></code>

This will attempt to insert the User record into the database with a ID of '1'.

[[Category:Configuration]]