Is the 'as' keyword required in Oracle to define an alias?

sql oracle alias required
Jonathan picture Jonathan · Dec 9, 2011 · Viewed 146.6k times · Source

Is the 'AS' keyword required in Oracle to define an alias name for a column in a SELECT statement?

I noticed that 

SELECT column_name AS "alias"

is the same as

SELECT column_name "alias"

I am wondering what the consequences are of defining a column alias in the latter way.

Answer

Roger Lindsjö picture Roger Lindsjö · Dec 9, 2011

According to the select_list Oracle select documentation the AS is optional.

As a personal note I think it is easier to read with the AS

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