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AS ​

Imagine you have a list of movies and you want to rename the column headings to make them more readable or relevant for your query results. This is where the AS keyword shines. Here's a simple example to illustrate:

sql
SELECT name AS 'Titles'
FROM movies;

Can you guess what AS does in this context?

The Power of AS ​

AS is a keyword in SQL that allows you to rename a column or a table using an alias. Think of it as a temporary name tag you give to your columns or tables to make your data easier to understand. The new name can be anything you want, as long as you enclose it in single quotes. In our example above, we renamed the name column to Titles.

Key Points to Remember ​

  • Use Single Quotes: Although it's not always necessary, it's best practice to surround your aliases with single quotes. This ensures clarity and prevents errors, especially in SQLite.

  • Database Specifics: This practice of using single quotes is specific to SQLite, the relational database management system (RDBMS) we're using in this exercise. Other RDBMSs like PostgreSQL might not require quotes or might use double quotes instead.

  • Temporary Rename: It's important to note that using AS doesn't rename the column in the table itself. The alias only appears in the result of your query. So, don't worry about making permanent changes to your database structure.

Activity ​

Let's put this knowledge into practice with a couple of fun activities.

Rename a Column ​

First, let's showcase what the AS keyword does. Select the name column from the movies table and rename it with an alias of your choosing. Here's the template to get you started:

sql
SELECT name AS 'YourAlias'
FROM movies;

NOTE: Replace 'YourAlias' with any name you prefer. Once you run the query, observe how the column name in the result set changes to your chosen alias.

title
1408
3 Men and a Baby
A Beautiful Mind
Air Force One
Aladdin
...

Rename Another Column ​

Now, let's take it a step further. Instead of selecting and renaming the name column, let's select the imdb_rating column and rename it as IMDb. Here's how you can do it:

sql
SELECT imdb_rating AS 'IMDb'
FROM movies;

After running this query, you'll see the imdb_rating column is now displayed as IMDb in your results.

IMDb
7.9
7.3
8.1
9.0
6.6
...