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Renaming Columns - SQL
SQL has no direct counterpart of RENAME. To derive the table on the right in Figure 4.4 from the table on the left, Tutorial D has IS_CALLED RENAME ( StudentId AS Sid ).
Figure: Tables differing only in a column name
It shows how the same effect can be achieved in SQL. Note that the SELECT clause has to include all the columns that are not subject to renaming, as well as those that are.
Example: Renaming a column
SELECT StudentId AS Sid, Name
FROM IS_CALLED
Explanation
SQL allows the result to have two or more columns of the same name. For example, if we replace Sid by Name in Example, we still have a valid SQL SELECT expression.
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