MySQL: Using Aliases & Old Names

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In MySQL, when an attribute or relation is renamed using the keyword AS, the alias is not stored in the database and cannot be used outside the query where it was defined. The original name of the attribute or relation can still be used, but the alias cannot. For example, using an alias in a query works within that query, but attempting to reference the original name alongside the alias in the same context can lead to errors, such as "Unknown column." If there is a need for persistent aliases, creating a view is recommended as it allows for the use of global aliases for columns or tables.
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If you rename an attribute or a relation with the keyword AS in MYSQL can you use the alias created outside the query where you renamed the attribute, also can you use the old name?
 
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EdmureTully said:
If you rename an attribute or a relation with the keyword AS in MYSQL can you use the alias created outside the query where you renamed the attribute, also can you use the old name?

Not that I am aware of.
 
The database does not store aliases you used in some query.

also can you use the old name?
Interesting, I never tried that. It is not possible.

SELECT * FROM `tablename` AS t WHERE t.fieldname=1 -> works
SELECT * FROM `tablename` WHERE tablename.fieldname=1 -> works
SELECT * FROM `tablename` AS t WHERE tablename.fieldname=1 -> does not work ("Unknown column 'tablename.fieldname' in 'where clause'")
 
If you have some good reason for having external (global) aliases to columns or tables then you can create a view
 
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