filter out apps without queries
filter out apps without queries

cmu-db/db-webcrawler,cmu-db/db-webcrawler,cmu-db/cmdbac,cmu-db/db-webcrawler,cmu-db/cmdbac,cmu-db/db-webcrawler,cmu-db/cmdbac,cmu-db/db-webcrawler,cmu-db/cmdbac,cmu-db/cmdbac