Checks whether the named filter exists.
emr_filter.exists(filter)
filter name
'TRUE', if the named filter exists, otherwise 'FALSE'.
This function checks whether the named filter exists.
emr_db.init_examples()
#> NULL
emr_filter.create("f1", "dense_track", time.shift = c(2, 4))
emr_filter.exists("f1")
#> [1] TRUE