"flat_key","key","int_value","string_value"
"chrome_trigger.name","chrome_trigger.name","[NULL]","study_name1"
"chrome_trigger.name","chrome_trigger.name","[NULL]","study_name2"
"chrome_trigger.name_hash","chrome_trigger.name_hash",10,"[NULL]"
"chrome_trigger.name_hash","chrome_trigger.name_hash",20,"[NULL]"
"chrome_trigger.name_hash","chrome_trigger.name_hash",30,"[NULL]"