Hi, I am MATSUDA Daiki and work at Miracle Linux in Japan, which company
provides the support for Zabbix!

Trigger included nodata func is evaluated as Failed at the first time is spite of
the item's valua are taken continuouly well.
Because, in DBget_item_from_db() at src/libs/zbxdbhigh/db.c, when row[16] is
null, item->lastclock is set to 0.

So, I attached the patches for 2.0.4 and 1.8.15.