Use JayDeBeApi to access PostgreSQL Data in Python

Access PostgreSQL data with Python scripts and standard SQL on any machine where Python and Java can be installed. You can use the CData JDBC Driver for PostgreSQL and the JayDeBeApi module to work with remote PostgreSQL data in Python. By using the CData Driver, you are leveraging a driver written for industry-proven standards to access your data in the popular Python language. This article shows how to use the driver to execute SQL queries to PostgreSQL and visualize PostgreSQL data with standard Python.

Use the JayDeBeApi module

JayDeBeApi is a Python library that serves as a JDBC (Java Database Connectivity) bridge, allowing Python programs to interact with Java databases, including CData JDBC Drivers. Use the pip install command to install the module:

pip install JayDeBeApi

Create the JDBC URL

Once you have JayDeBeApi installed, you are ready to work with PostgreSQL data in Python using SQL.

To connect to PostgreSQL, set the Server, Port (the default port is 5432), and Database connection properties and set the User and Password you wish to use to authenticate to the server. If the Database property is not specified, the data provider connects to the user's default database.

SSH Connectivity for PostgreSQL

You can use SSH (Secure Shell) to authenticate with PostgreSQL, whether the instance is hosted on-premises or in supported cloud environments. SSH authentication ensures that access is encrypted (as compared to direct network connections).

SSH Connections to PostgreSQL in Password Auth Mode

To connect to PostgreSQL via SSH in Password Auth mode, set the following connection properties:

• User: PostgreSQL User name
• Password: PostgreSQL Password
• Database: PostgreSQL database name
• Server: PostgreSQL Server name
• Port: PostgreSQL port number like 3306
• UserSSH: "true"
• SSHAuthMode: "Password"
• SSHPort: SSH Port number
• SSHServer: SSH Server name
• SSHUser: SSH User name
• SSHPassword: SSH Password

SSH Connections to PostgreSQL in Public Key Auth Mode

To connect to PostgreSQL via SSH in Password Auth mode, set the following connection properties:

• User: PostgreSQL User name
• Password: PostgreSQL Password
• Database: PostgreSQL database name
• Server: PostgreSQL Server name
• Port: PostgreSQL port number like 3306
• UserSSH: "true"
• SSHAuthMode: "Public_Key"
• SSHPort: SSH Port number
• SSHServer: SSH Server name
• SSHUser: SSH User name
• SSHClientCret: the path for the public key certificate file

Built-in Connection String Designer

For assistance in constructing the JDBC URL, use the connection string designer built into the PostgreSQL JDBC Driver. Either double-click the JAR file or execute the jar file from the command-line.

java -jar cdata.jdbc.postgresql.jar

Fill in the connection properties and copy the connection string to the clipboard.

👁 Using the built-in connection string designer to generate a JDBC URL (Salesforce is shown.)

Below is a sample variable assignment, including a typical JDBC connection string:

jdbc_url = "jdbc:postgresql:User=postgres;Password=admin;Database=postgres;Server=127.0.0.1;Port=5432;"

Access PostgreSQL data in Python

With the JDBC URL configured, you only need the absolute path to the JDBC driver JAR file, which is in the "lib" folder in the installation directory ("C:\Program Files\CData[product_name] 20XX\lib\cdata.jdbc.postgresql.jar" on Windows).

NOTE: If you haven't already, set the JAVA_HOME environment variable to the Java installation directory.

Use code similar to the follow to read and print data from PostgreSQL:

import jaydebeapi

#The JDBC connection string
jdbc_url = "jdbc:postgresql:User=postgres;Password=admin;Database=postgres;Server=127.0.0.1;Port=5432;"

username = "****"
password = "****"

#The absolute Path to the JDBC driver JAR file, typically:
jdbc_driver_jar = "C:\Program Files\CData[product_name] 20XX\lib\cdata.jdbc.postgresql.jar"

conn = jaydebeapi.connect(
 "cdata.jdbc.postgresql.PostgreSQLDriver",
 jdbc_url,
 [username, password],
 jdbc_driver_jar,
)

cursor = conn.cursor()
cursor.execute("SELECT * FROM Orders;")


results = cursor.fetchall()
for row in results:
 print(row)

cursor.close()
conn.close()

Free trial & more information

Download a free, 30-day trial of the CData JDBC Driver for PostgreSQL and start working with your live PostgreSQL data in Python. Reach out to our Support Team if you have any questions.