Python drivers

• YugabyteDB Psycopg2
• PostgreSQL Psycopg2

The Yugabyte Psycopg2 smart driver is a distributed Python driver for YSQL, built on the PostgreSQL psycopg2 driver. Although the upstream PostgreSQL psycopg2 driver works with YugabyteDB, the Yugabyte driver is cluster- and topology-aware, and eliminates the need for external load balancers.

CRUD operations with YugabyteDB psycopg2 driver

Learn how to establish a connection to YugabyteDB database and begin basic CRUD operations using the steps in the Build an application page under the Quick start section.

The following sections break down the quick start example to demonstrate how to perform common tasks required for Python application development using the YugabyteDB Psycopg2 driver.

After completing these steps, you should have a working Python application that uses Psycopg2 to connect to your cluster, set up tables, run queries, and print out results.

Step 1: Add the YugabyteDB driver dependency

Building Psycopg requires a few prerequisites (a C compiler and some development packages). Check the installation instructions and the FAQ for details.

The YugabyteDB Psycopg2 requires PostgreSQL version 11 or above (preferably 14).

Once you've installed the prerequisites, you install psycopg2-yugabytedb like any other Python package, using pip to download it from PyPI:

$ pip install psycopg2-yugabytedb

Or, you can use the setup.py script if you've downloaded the source package locally:

$ python setup.py build
$ sudo python setup.py install

Step 2: Connect to your cluster

First, import the psycopg2 package.

import psycopg2

You can provide the connection details as a string, or as a dictionary.

• Connection string:

  "dbname=database_name host=hostname port=port user=username  password=password load_balance=true"
  

• Connection dictionary:

  user = 'username', password='xxx', host = 'hostname', port = 'port', dbname = 'database_name', load_balance='True'
  

Here's a sample call to connect to YugabyteDB:

conn = psycopg2.connect(dbname='yugabyte',host='localhost',port='5433',user='yugabyte',password='yugabyte', load_balance='True')

Use SSL

Use the following example URL for connecting to a YugabyteDB cluster with SSL enabled:

conn = psycopg2.connect("host=<hostname> port=5433 dbname=yugabyte user=<username> password=<password> load_balance=true sslmode=verify-full sslrootcert=/Users/my-user/Downloads/root.crt")

If you have created a cluster on YugabyteDB Managed, follow the steps to obtain the cluster connection parameters and SSL Root certificate.

Step 3: Query the YugabyteDB cluster from your application

1. Create a new Python file called QuickStartApp.py in the base package directory of your project.

2. Copy the following sample code to set up tables and query the table contents. Replace the connection string yburl with the cluster credentials and SSL certificate, if required.

import psycopg2

# Create the database connection.

yburl = "host=127.0.0.1 port=5433 dbname=yugabyte user=yugabyte password=yugabyte load_balance=True"

conn = psycopg2.connect(yburl)

# Open a cursor to perform database operations.
# The default mode for psycopg2 is "autocommit=false".

conn.set_session(autocommit=True)
cur = conn.cursor()

# Create the table. (It might preexist.)

cur.execute(
  """
  DROP TABLE IF EXISTS employee
  """)

cur.execute(
  """
  CREATE TABLE employee (id int PRIMARY KEY,
                         name varchar,
                         age int,
                         language varchar)
  """)
print("Created table employee")
cur.close()

# Take advantage of ordinary, transactional behavior for DMLs.

conn.set_session(autocommit=False)
cur = conn.cursor()

# Insert a row.

cur.execute("INSERT INTO employee (id, name, age, language) VALUES (%s, %s, %s, %s)",
            (1, 'John', 35, 'Python'))
print("Inserted (id, name, age, language) = (1, 'John', 35, 'Python')")

# Query the row.

cur.execute("SELECT name, age, language FROM employee WHERE id = 1")
row = cur.fetchone()
print("Query returned: %s, %s, %s" % (row[0], row[1], row[2]))

# Commit and close down.

conn.commit()
cur.close()
conn.close()

When you run the QuickStartApp.py project, you should see output similar to the following:

Created table employee
Inserted (id, name, age, language) = (1, 'John', 35, 'Python')
Query returned: John, 35, Python

If there is no output or you get an error, verify the parameters included in the connection string.

Next steps

• Learn how to build Python applications using Django
• Learn how to build Python applications using SQLAlchemy
• Learn more about fundamentals of the YugabyteDB Psycopg2 Driver