public function testIsModifiedAndNullValues()
{
$a = new Author();
$a->setFirstName('');
$a->setLastName('Bar');
$a->setAge(0);
$a->save();
$a->setFirstName(null);
$this->assertTrue($a->isModified(), "Expected Author to be modified after changing empty string column value to NULL.");
$a->setAge(null);
$this->assertTrue($a->isModified(), "Expected Author to be modified after changing 0-value int column to NULL.");
$a->setFirstName('');
$this->assertTrue($a->isModified(), "Expected Author to be modified after changing NULL column value to empty string.");
$a->setAge(0);
$this->assertTrue($a->isModified(), "Expected Author to be modified after changing NULL column to 0-value int.");
}
