psycopg2 : Query Postgis Function

Question

I want to do Query : SELECT ST_AsText(ST_MakePoint(-7.83753572095, 110.354612964)) ;

my python code =

import psycopg2

conn = psycopg2.connect(dbname = 'gis02', host= '127.0.0.1', user = 'gis2user',password= '123456')
cur = conn.cursor()

pointA={}
pointA['lat']=-7.83753572095
pointA['lon']=110.354612964

myquery = 'SELECT ST_AsText(ST_MakePoint(%s, %s)) ;'
pointA['geom']= cur.execute(myquery %(pointA['lat'], pointA['lon'])).fetchone()

The result is :

AttributeError: 'NoneType' object has no attribute 'fetchone'

when I do it directly in psql console I got :

POINT(-7.83753572095 110.354612964)

How to call Postgis's functions using psycopg2 ?

Answer 1

fetchone() is not a method of cur.execute() but of the cursor class (here: cur). So you cannot combine this in one line.

You need to first execute and then fetchone.

cur.execute(myquery %(pointA['lat'], pointA['lon']))
pointA['geom'] = cur.fetchone()

---

execute(query, vars=None):
The method returns None. If a query was executed, the returned values can be retrieved using fetch*() methods.