PostgreSQL doesn't recognize function called from Python

Question

I have a function in PostgreSQL:

func(a integer, b integer)

When I call the function from Python:

"select * from func(%s,%s)"(a_1,b_1)

It works if a_1 and b_1 are integers. However there can be a case where b_1 is None. In this case I get this error message:

Exception: ERROR: column "none" does not exist LINE 1: ...func(38,None)

I know that None in Python is equivalent to PostgreSQL NULL, but in this case I don't know how to solve it.

Is it possible that a_1 or b_1 is anything other than an integer? Say, a string? Particularly a string such as '); DROP TABLE Something --' — Kevin
– Kevin, Commented Nov 29, 2016 at 7:36
@Kevin a_1 and b_1 data is received from integer fields in other DB. — avi
– avi, Commented Nov 29, 2016 at 9:07

clemens · Accepted Answer · 2016-11-29 06:42:18Z

1

"select * from func(%s,%s)" % (a_1, 'NULL' if b_1 == None else b_1)

answered Nov 29, 2016 at 6:42

clemens

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