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PostgreSQL NOT Operator/Condition With Examples

The NOT operator is a frequently used operator in Postgres that negates a boolean expression. It allows us to filter or exclude certain data from the query’s result set.

PostgreSQL Numeric Data Type With Practical Examples

In PostgreSQL, the NUMERIC data type is a more precise data type used to store decimal values. It can be defined with specific precision and scale.

How to List Sessions/Active Connections in PostgreSQL

Postgres allows you to find the list of active connections on your database server via the "pg_stat_activity" and pgAdmin's "Server Activity panel”.

How to Show List of All Databases and Tables in PostgreSQL

In Postgres, the “\l”, “\list”, and “pg_catalog” are used to show the list of databases, while the “\dt” and “pg_catalog.pg_table” are used to show the list of relations.

Date Time Functions in PostgreSQL With Examples

Postgres offers a wide range of built-in functions to efficiently manipulate date and time values. For instance, NOW(), TO_TIMESTAMP(), CURRENT_DATE, etc.

How to Add Days to a Date in PostgreSQL

Postgres allows us to add a certain number of days to a date field using the plus “+” operator. It retrieve a new date representing the original date plus the specified number of days.

PostgreSQL TIMESTAMP Data Types and Functions

PostgreSQL provides two temporal data types to deal with the TIMESTAMPS: TIMESTAMP(without the time zone) and TIMESTAMPTZ(with a time zone).

How to Find the Interval Between Two Dates in PostgreSQL

In PostgreSQL, finding the interval between two dates can be accomplished using the built-in AGE() function or the minus “-” operator.

How to Convert a TIMESTAMP to String in PostgreSQL

PostgreSQL provides a built-in TO_CHAR() function that converts the given timestamp to a string. It utilizes a format mask to convert the input value to a string.

How to Extract DOW in PostgreSQL?

In PostgreSQL, the EXTRACT() and DATE_PART() functions are used to extract a DOW(an acronym for Day of Week) from a date or timestamp.