Postgres and Open Source Experts

Postgres provides the “CREATE VIEW”, “CREATE OR REPLACE VIEW”, and “DROP VIEW” statements to create, update or drop a view from the database.

The POWER() or POW() function accepts two numeric values as arguments and retrieves the first value raised to the power of the second value.

To sort the table’s data into a specific format, the ORDER BY clause is used in Postgres. Postgres users must use the ORDER BY clause on the DATE type column to sort the table data by date.

ALIASES are used in Postgres to provide a temporary name to the columns, tables, etc., while executing/writing Postgres queries.

In Postgres, the “column doesn’t exist” error occurs because of various reasons, such as the searched column doesn’t exist, typo mistakes, column alias being used incorrectly, etc.

To define an auto-incremented primary key in Postgres, specify a column name followed by a pseudo data type named “SERIAL”, and then specify the PRIMARY KEY keyword.

PostgreSQL offers an ARRAY_TO_STRING() function that accepts three arguments: an array, a delimiter, and a text to replace the null values.

The TRUNC() function trims the whole fractional part or up to specified precision, while the ROUND() function rounds the input number to the nearest integer/specified fractional places.

PostgreSQL allows us to create a string array using one of three data types: CHAR, VARCHAR, and TEXT. Once an array is created, various operations can be performed on that array.

ARRAY_REMOVE() function accepts an array and a specific number as arguments and deletes all the occurrences of that particular number from the input array.