How do i seach an sql column for data that already exists from python?

Question

New to python and even newer to sql and i'm simply trying to check sql for usernames that already exists for a log in program but can't quite figure it out. Here's my code:

def validuser():
cursor.execute("SELECT username FROM OCRflix EXISTS")
if cursor.execute == 0:
    print("That username already exists")
else:
    print("secure password")

I'm aware of sql injection but this is just practise and wont be used, thanks!

Answer 1

sql = 'select exists(select 1 from OCRflix where username = ? limit 1)'
cursor.execute(sql, (myUsername,));

if cursor.fetchone()[0] == 1:
    # username found
    pass
else:
    # username not found
    pass

Answer 2

You can try this

sql = "SELECT username FROM OCRflix WHERE username=?"
result = cursor.execute(sql, (user_input,)

if result:
   print("Username already exits")
else:
   print("secure Password")

the above program checks if the user input is already present in the username column.