Alias

 Alias

When we JOIN tables together, it is nice to give each table an alias. Frequently an alias is just the first letter of the table name. You actually saw something similar for column names in the Arithmetic Operators concept.


Example:


FROM tablename AS t1
JOIN tablename2 AS t2


Before, you saw something like:


SELECT col1 + col2 AS total, col3


Frequently, you might also see these statements without the AS statement. Each of the above could be written in the following way instead, and they would still produce the exact same results:


FROM tablename t1
JOIN tablename2 t2


and


SELECT col1 + col2 total, col3


Aliases for Columns in Resulting Table

While aliasing tables is the most common use case. It can also be used to alias the columns selected to have the resulting table reflect a more readable name.

Example:


Select t1.column1 aliasname, t2.column2 aliasname2
FROM tablename AS t1
JOIN tablename2 AS t2


The alias name fields will be what shows up in the returned table instead of t1.column1 and t2.column2


aliasname               aliasname2
example row               example row
example row               example row

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