Postgres and Open Source Experts

In Postgres, the IS NOT NULL operator tests whether an expression or a column contains a non-null value. It is used in a SELECT statement to return only non-null records from a column.

Use the “connect()” method of “psycopg” module to establish a connection with the Postgres database using python. Next, create a cursor object and execute the INSERT query via the cursor object.

The Secure Shell Protocol (SSH) provides IT professionals with a secure method to remotely connect to client environments. SSH typically uses a password or public-key method to encrypt connections and authenticate network devices. This tutorial will focus on establishing an SSH connection for data transfer between the postgres users on two Ubuntu 22.04 LTS instances.

In PostgreSQL, the UPPER(), LOWER(), and INITCAP() functions are used for letter case conversion.

The SPLIT_PART() function accepts three arguments: a string, a delimiter/separator, and a position. Consequently, it retrieves the extracted data from the given string.

PostgreSQL offers various built-in functions to group data by time, such as the DATE_TRUNC(), EXTRACT(), and DATE_PART() functions.

PostgreSQL has three main logical operators: OR, AND, and NOT. All these operators retrieve a boolean value and are hence also referred to as Boolean operators.

To drop/remove the default value from a column, you need to use the “DROP DEFAULT” keyword with the assistance of the “ALTER TABLE” command.

PostgreSQL provides several integer data types, such as INTEGER, SMALLINT, and BIGINT. These data types assist us in storing and manipulating whole numbers.

In Postgres, the DROP VIEW statement allows us to delete one or more views from a database. To do that, use the DROP VIEW statement followed by the view’s name to be deleted.