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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.

PostgreSQL SELECT INTO Statement With Examples

In PostgreSQL, the SELECT INTO statement creates a new table, copies data from the original table, and pastes it into the newly created table.

PostgreSQL RANK() Function With Examples

Postgres has a built-in Window function called RANK() that assigns a rank to every single row within a partition.