psycopg2 how deal with TypeError: not all arguments converted during string formatting

Question

i have a simple database query by psycopg2 but i do not know why it always show errors here is the code

ip =\"127.0.0.1\"
 sql=\"select count(*) from radacct         


        

Answer 1

The sql arguments you pass to execute must be in a tuple or list, even if there's only one of them. This is noted in the documentation:

For positional variables binding, the second argument must always be a sequence, even if it contains a single variable. And remember that Python requires a comma to create a single element tuple:

So you need to do it like this:

ip ="127.0.0.1" 
sql="select count(*) from radacct where nasipaddress=%s"
cur.execute(sql, (ip,))