AutoAddPk Behavior

The auto_add_pk behavior adds a primary key columns to the tables that don’t have one. Using this behavior allows you to omit the declaration of primary keys in your tables.

Basic Usage

In the schema.xml, use the <behavior> tag to add the auto_add_pk behavior to a table:

<table name="book">
  <column name="title" type="varchar" required="true" primaryString="true" />
  <behavior name="auto_add_pk" />
</table>

Rebuild your model, and insert the table creation sql. You will notice that the book table has two columns and not just one. The behavior added an id column, of type integer and autoincremented. This column can be used as any other column:

<?php
$b = new Book();
$b->setTitle('War And Peace');
$b->save();
echo $b->getId(); // 1

This behavior is more powerful if you add it to the database instead of a table. That way, it will alter all tables not defining a primary key column - and leave the others unchanged.

<database name="bookstore" defaultIdMethod="native">
  <behavior name="auto_add_pk" />
  <table name="book">
    <column name="title" type="varchar" required="true" primaryString="true" />
  </table>
</database>

Parameters

By default, the behavior adds a column named id to the table if the table has no primary key. You can customize all the attributes of the added column by setting corresponding parameters in the behavior definition:

<database name="bookstore" defaultIdMethod="native">
  <behavior name="auto_add_pk">
    <parameter name="name" value="identifier" />
    <parameter name="autoIncrement" value="false" />
    <parameter name="type" value="bigint" />
  </behavior>
  <table name="book">
    <column name="title" type="varchar" required="true" primaryString="true" />
  </table>
</database>

Once you regenerate your model, the column is now named differently:

<?php
$b = new Book();
$b->setTitle('War And Peace');
$b->setIdentifier(1);
$b->save();
echo $b->getIdentifier(); // 1