Postgres and Open Source Experts

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”.

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.

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

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

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

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.

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.

In Postgres, a built-in function named TO_CHAR() is used to convert any data type, such as an integer, interval, timestamp, date, etc., to a string.

The CURRENT_TIME function retrieve the current time and the time zone. It can accept an optional parameter “precision” to set the precision of the retrieved fractional seconds.