-bash-4.2$ mysql -u zabbix -p zabbix_proxy
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mysql> select dcheckid,druleid,type,key_ from dchecks where druleid in (select druleid from drules where name="DMZ");
+----------+---------+------+--------------+
| dcheckid | druleid | type | key_         |
+----------+---------+------+--------------+
|        7 |       5 |   12 |              |
|        8 |       5 |    9 | system.uname |
+----------+---------+------+--------------+
2 rows in set (0.05 sec)

mysql> select dserviceid,dhostid,status,dcheckid from dservices where dcheckid in (select dcheckid from dchecks where druleid in (select druleid from drules where name="DMZ"));
Empty set (0.01 sec)

mysql>