Postgres DELETE不使用子查询

Question

我正在编写一个函数来删除与某个查询匹配的所有行。

如果我选择匹配的行ID，然后分两步删除带有id的行，那么它就可以了。因此，我知道我对查找要删除的行的查询是正确的：

    sql = """SELECT MSN.id
                 FROM schedule_missingschedulenames as MSN,
                      names_parsedname as PN,
                      names_simplifiednamemapping as SNM,
                      names_canonicalname as CN
                WHERE MSN.parsed_name_id = PN.id
                  AND PN.simplified_name = SNM.simplified_name
                  AND SNM.canonical_name_id = CN.id
                  AND CN.category_id = %s""" % cat.id

    ids = [row.id for row in MissingScheduleNames.objects.raw(sql)]
    MissingScheduleNames.objects.filter(id__in=ids).delete()

但是，如果我尝试在一个查询中执行DELETE，它就不起作用：

    sql = """DELETE FROM schedule_missingschedulenames WHERE id in (SELECT MSN.id
                 FROM schedule_missingschedulenames as MSN,
                      names_parsedname as PN,
                      names_simplifiednamemapping as SNM,
                      names_canonicalname as CN
                WHERE MSN.parsed_name_id = PN.id
                  AND PN.simplified_name = SNM.simplified_name
                  AND SNM.canonical_name_id = CN.id
                  AND CN.category_id = %s)""" % cat.id
    MissingScheduleNames.objects.raw(sql)

第二个查询根本不会删除任何内容。

DELETE查询在哪里出错了？