select * from zabbix.sessions; delete from sessions;

0 - session active
1 - session is not active

List inactive sessions:

select * from zabbix.sessions where status='1';

List all active sessions:

select * from zabbix.sessions where status='0';

List 10 oldest sessions:

select * from zabbix.sessions order by lastaccess limit 10;

+----------------------------------+--------+------------+--------+
| sessionid                        | userid | lastaccess | status |
+----------------------------------+--------+------------+--------+
| 42170f1df0f7a1089c6ea3e4a80c30ec |      2 | 1526412503 |      0 |
| 49ca638b10a0939965812bc8e6b2ca31 |      2 | 1526412503 |      0 |
| d5794c5112870fb16b1f39c2ef4ced89 |      2 | 1526412503 |      0 |
| c202f885c52b75d1b4abafead6925957 |      2 | 1526412563 |      0 |
| cad8c323ce65bea7b8d28d2ed12ab574 |      2 | 1526412564 |      0 |
| f1f52e8c2368470f15677026bc526d37 |      2 | 1526412564 |      0 |
| 99f4b75abc4a6991f7332e6001a33ed2 |      2 | 1526412624 |      0 |
| 0380355a548b008f3e069383c45a4ed6 |      2 | 1526412624 |      0 |
| 0a6279153e1dc3d1ba594852cda17efe |      2 | 1526412624 |      0 |
| 6f981f1fa7b50825069354ba6a748027 |      2 | 1526412684 |      0 |
+----------------------------------+--------+------------+--------+

Delete some sessions:

delete from sessions where lastaccess<1526412684;

List all users:

SELECT userid FROM users;

Delete all sessions which has been generated by users which do not exist anymore:

DELETE FROM sessions WHERE NOT userid IN (SELECT userid FROM users);

Delete all content in the table but keep the structure:

DELETE FROM sessions;