postgres fetchone code example
Example 1: psycopg2 select example
import psycopg2
try:
connection = psycopg2.connect(user="sysadmin",
password="pynative@#29",
host="127.0.0.1",
port="5432",
database="postgres_db")
cursor = connection.cursor()
postgreSQL_select_Query = "select * from mobile"
cursor.execute(postgreSQL_select_Query)
print("Selecting rows from mobile table using cursor.fetchall")
mobile_records = cursor.fetchall()
print("Print each row and it's columns values")
for row in mobile_records:
print("Id = ", row[0], )
print("Model = ", row[1])
print("Price = ", row[2], "\n")
except (Exception, psycopg2.Error) as error :
print ("Error while fetching data from PostgreSQL", error)
finally:
#closing database connection.
if(connection):
cursor.close()
connection.close()
print("PostgreSQL connection is closed")
Example 2: postgresql psycopg2 select single value
#!/usr/bin/env python
# -*- coding: utf-8 -*-
import psycopg2
import sys
con = None
try:
con = psycopg2.connect(database='testdb', user='postgres',
password='s$cret')
cur = con.cursor()
cur.execute('SELECT version()')
version = cur.fetchone()[0]
print(version)
except psycopg2.DatabaseError as e:
print(f'Error {e}')
sys.exit(1)
finally:
if con:
con.close()