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.
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This is the Education section of the Command Prompt Website. Here you will find blogs specifically about how to use Postgres and related technologies.
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.
This blog post explained date data types, functions, operators, formats, and intervals with the help of appropriate examples.
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.