Function truncate_name

django/db/backends/utils.py:283–301

Shorten an SQL identifier to a repeatable mangled version with the given length. If a quote stripped name contains a namespace, e.g. USERNAME"."TABLE, truncate the table portion only.

(identifier, length=None, hash_len=4)

def truncate_name(identifier, length=None, hash_len=4):
    """
    Shorten an SQL identifier to a repeatable mangled version with the given
    length.

    If a quote stripped name contains a namespace, e.g. USERNAME"."TABLE,
    truncate the table portion only.
    """
    namespace, name = split_identifier(identifier)

    if length is None or len(name) <= length:
        return identifier

    digest = names_digest(name, length=hash_len)
    return "%s%s%s" % (
        '%s"."' % namespace if namespace else "",
        name[: length - hash_len],
        digest,
    )


def names_digest(*args, length):