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Databases SQL Basics Getting Data from a Database Categorizing Your Output with 'AS'

Why and when would we need to use aliases?

A real world example would be great!

1 Answer

Steven Parker
Steven Parker
231,248 Points

Aliases are useful in many situations, but two spring to mind immediately:

When creating a column using functions and/or concatenation:

SELECT first_name || " " || last_name AS "Full Name"  -- otherwise the column header is ugly
FROM sometable

And when joining tables with long names:

SELECT c.name, s.date, s.item  -- this would be much longer without aliases
FROM customers_listing AS c
JOIN quarterly_sales_data AS s
  ON c.id = s.customer_id      -- this would be longer too