def sync_created_constraints(src, dest):
    """Generate the SQL statements needed to ADD constraints
       (indexes, foreign keys) to the target table (patch)
       and remove them (revert)

    Args:
        src: A OrderedDictionary of SchemaObject IndexSchema
             or ForeignKeySchema Instances
        dest: A OrderedDictionary of SchemaObject IndexSchema
              or ForeignKeySchema Instances

    Yields:
        A tuple (patch, revert) containing the next SQL statements
    """
    for c in src:
        if c not in dest:
            yield src[c].create(), src[c].drop()
