$conditions = array(
'OR' => array(
array( 'MemberRole.school_id' => array()),
array( 'MemberRole.role_id' => $role),
);
);
'OR' => array(
array(
'MemberRole.school_id' => array(),
'MemberRole.role_id' => $role,
),
array(
'MemberRole.school_id' => array(),
'MemberRole.role_id' => Environment::read('role.register'),
),
array(
'MemberRole.school_id' => $school_id,
'MemberRole.role_id' => Environment::read('role.register'),
),
array(
'MemberRole.school_id' => $school_id,
'MemberRole.role_id' => $role
)
)