areatrigger_involvedrelation table holds connections between
triggers and quests.
If there is a record in the table for a quest, the quest will not be completed until the player activates the areatriger. The quest is not necessarily finished after that, but that one condition of the quest is satisfied. If the only condition of the quest is to explore an area, then the quest will be complete.
An areatrigger identifier. The value has to match with a areatrigger identifier defined in AreaTrigger.dbc.