Postgres and Open Source Experts

In PostgreSQL, the pg_size_pretty() function retrieves the size of the database object in a human-readable format, such as KB, MB, etc.

LPAD() or “left padding” is a built-in function in Postgres which fills a string of a specific length with a substring. It fills/pads the given string from the left side.

In Postgres, the RANDOM() is an in-built function that generates a random numeric value between “0(inclusive)” and “1(exclusive)” or between a specific range.

To format a timestamp, specify a timestamp and a valid format as arguments to the Postgres TO_CHAR() function.

In PostgreSQL, to convert the epoch time to a timestamp, pass the EPOCH time as an argument to the TO_TIMESTAMP() function.

Postgres allows us to set a TIMESTAMP as the column’s default value. For this purpose, the DEFAULT keyword is used with the column name at the time of table creation.

To compare arrays in PostgreSQL, the equality operators, ordering operators, containment operators, and overlap operators are used.

In PostgreSQL, to extract epoch time from the current or specific time, the EXTRACT() function is used with the EPOCH argument.

To check the PostgreSQL version in Ubuntu, use the "SQL Shell" (psql) tool, “pg_config”, “dpkg”, or “apt-cache” commands.

In PostgreSQL, the “+” operator is used to add minutes to the current or specific DateTime values. Where the DateTime value can be a date, interval, time, or timestamp.