Extension:Newsletter/nl_issues table

mysql> describe nl_issues;
+-------------------+------------------+------+-----+---------+-------+
| Field             | Type             | Null | Key | Default | Extra |
+-------------------+------------------+------+-----+---------+-------+
| nli_issue_id      | int(10) unsigned | NO   | PRI | NULL    |       |
| nli_page_id       | int(11)          | NO   |     | NULL    |       |
| nli_newsletter_id | int(11)          | NO   | PRI | NULL    |       |
| nli_publisher_id  | int(11)          | NO   |     | NULL    |       |
+-------------------+------------------+------+-----+---------+-------+