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What is Postgres (summary)

PostgreSQL, often referred to simply as "Postgres," is a popular open-source relational database management system (RDBMS). It is known for its stability, robustness, and support for a wide range of advanced features, making it a popular choice for large-scale, high-performance applications.

PostgreSQL was first released in 1996 as an Open Source project by the PostgreSQL Global Development Group. It is a fork of work done on Ingres and later Postgres …

PostgreSQL DATEDIFF - DateTime Difference in Years, Months, etc

The “-” operator, DATE_PART(), EXTRACT(), and AGE() functions can be used in PostgreSQL to calculate the difference between various DateTime values.

How to Start or Stop PostgreSQL Server on Ubuntu

In Ubuntu, “/etc/init.d/postgresql” and the “systemctl” commands are used with the “start” or “stop” option to activate or deactivate the Postgres server, respectively.

Composite Primary Keys in PostgreSQL

In PostgreSQL, a composite primary key can be defined as a combination of two or more columns that guarantees the uniqueness of a record.

How to Fix psql Command Not Found Error in PostgreSQL?

In PostgreSQL, the “psql command not found” error arises if Postgres is not installed or the path for Postgres tools is not set on your system.

How to Use the pg_sleep() Function in PostgreSQL

In PostgreSQL, the pg_sleep() function accepts the fractional seconds as arguments and delays the execution until the specified seconds pass

How to Use TRIM_ARRAY() Function in PostgreSQL

In PostgreSQL, the TRIM_ARRAY() function trimmed the specified number of elements from the end of the given array and return a newly updated array.

How to Join Three Tables in PostgreSQL

PostgreSQL uses the INNER JOIN to get matching results from two or more tables based on the defined join conditions.

How to Get/Check Yesterday’s Date in PostgreSQL

In Postgres, there is no such function that directly retrieves yesterday’s date. However, any Postgres function that returns today’s date can be used with the “-” operator to get yesterday’s date.

How to Uninstall PostgreSQL on CentOS?

To uninstall PostgreSQL from CentOS, execute the “yum remove postgresql-server postgresql-contrib” command.