有人能帮我在Codeigniter迁移数据库中添加外键吗?这是代码:
public function up()
{
$this->dbforge->add_field(array(
'ID_PELAYANAN' => array(
'type' => 'INT',
'constraint' => 50,
'auto_increment' => TRUE
),
'THBLMUT' => array(
'type' => 'VARCHAR',
'constraint' => '6',
),
'ID_DIST' => array(
'type' => 'VARCHAR',
'constraint' => '2',
),
'ID_AREA' => array(
'type' => 'VARCHAR',
'constraint' => '5',
),
'ID_RAYON' => array(
'type' => 'VARCHAR',
'constraint' => '5',
),
'N_RAYON' => array(
'type' => 'CHAR',
'constraint' => '70',
),
));
$this->dbforge->add_key('ID_PELAYANAN', TRUE);
$this->dbforge->create_table('pelayanan');
}
public function down()
{
$this->dbforge->drop_table('pelayanan');
}
}
我想在这个表中将'ID_AREA'和'ID_RAYON'设置为外键,应该怎么解决?