python - Filter out if query returns nothing -


how can filter out results database can store data returns something.

i got following code:

mergedlist_uniques = [id1,id2,id3,id4,..] #list containing data  in range(0, 5):     cur = db.cursor()     cur.execute("select id `id_activities` `id_activities`.`id` = '" + mergedlist_uniques[i] + "' limit 1")     results = cur.fetchall()     if results != "":         print("empty, result is: ", results)         #data.append(results)

in if statement check whether results contains nothing not working.

i still following result:

>>> ('empty, result is: ', ())

what should expect whenever result is: () should not print if contains:

>>> ('empty, result is: ', (idx))

then should print out result.

what did wrong?

as per python documentation, none, 0, "", (), {}, [] treated false, use 

if results:     #do

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