Postgres and Open Source Experts

PostgreSQL provides various functions, such as LOWER(), INITCAP(), or UPPER(), to alter a string to lowercase, proper case, and uppercase, respectively.

PostgreSQL offers multiple date/time functions, such as CURRENT_DATE, NOW(), EXTRACT(), CURRENT_TIMESTAMP, etc. If we talk about the CURRENT_TIMESTAMP function, it retrieves the current date, time, and timezone when a transaction starts.

This write-up will present a thorough overview of the Postgres CURRENT_TIMESTAMP function with examples. So, let’s begin.

How to Use CURRENT_TIMESTAMP Function in PostgreSQL?

Firstly, let’s understand the syntax of the CURRENT_TIMESTAMP function:

CURRENT_TIMESTAMP(<precision>);

Here, “precision” is an optional …

In PostgreSQL, we can use the "DELETE USING" statement, subquery, or Postgres immediate table to delete duplicate rows from a table.

In PostgreSQL, the MIN() function retrieves a set's minimum value. Use the LEAST() function to get the minimum/least value from more than one column

PostgreSQL offers a built-in MAX() function that is used to retrieve the maximum value of a set. The MAX() function has multiple real-life implementations, such as fetching the highest-paid employee, finding a top-ranked student, and so on. So, let’s learn the working of the MAX() function through Practical examples.

How to Use MAX() Function in Postgres?

The below snippet will show you the basic syntax of the MAX() function:

MAX(exp); …

In PostgreSQL, the AVG() function is used to retrieve the average of a set. The DISTINCT operator is used with the AVG() function to find the average of distinct values.

The SUM() is used to perform the addition on a set of values. Use the DISTINCT option with the SUM() function to calculate the sum of distinct values.

The table rows can be counted using PostgreSQL's COUNT() function. It is an aggregate function that enables us to count the rows that meet the specified condition. There are multiple ways to use the COUNT() function, such as COUNT(*), COUNT(col_name), and COUNT(DISTINCT col_name). Each implementation of the COUNT() function serves a different functionality.

Let’s learn the working of the COUNT() function through Practical examples.

How to Use COUNT(*) Function in …

In PostgreSQL, to get the substring’s location in a string, the POSITION() function is used. It returns an integer that represents the substring’s location.

In PostgreSQL, the NOT IN operator filters the query results and returns all the values of a result set except the specified values.