I have a table "Performance" with device performance data of my app. The table has the following columns:

user-id, device-name, fps, time-stamp

Now I want to extract the devices which have "fps" below a threshold (let's say below 10), because I want to blacklist those devices. I want to check in every week and see if there are any "new devices" with less than 10 fps and add them to the blacklist.

say I have a second table "Blacklist", where I manually enter the devices I have so far blacklisted

• now a new record enters the "Performance" table
  
• I want to check if the "device-name" of that new record already exists in the "Blacklist" table and if not, hightlight the field, or set a flag in another field, e.g. "IsBlacklisted"

how to do that?