Can aliases be used for where in sql?

Using aliases in the WHERE clause in SQL

In SQL, the WHERE clause is used to filter and limit query results based on specific conditions. When using the WHERE clause, you usually need to reference column names in the table. For convenience and readability, you can use aliases in queries to specify abbreviations or short names for tables or columns.

Is it possible to use aliases in the WHERE clause?

Can. Using aliases in the WHERE clause is not only allowed, but in some cases recommended.

How to use aliases?

To use an alias, add the AS keyword after the table or column name and specify the desired alias. For example:

SELECT * FROM Customers AS C
WHERE C.CustomerID > 10;

In this example, the Customers table is given the alias C, and then the alias C is used in the WHERE clause to reference the table columns in .

Advantages of using aliases

• Improve readability: Aliases can make queries easier to read and understand, especially when querying When multiple tables or columns are involved.
• Avoid confusion: Aliases can help avoid confusion when table or column names are long or similar to column names in other tables.
• Simplify queries: Alias ​​can make queries more concise, especially when using complex expressions in the WHERE clause.

Notes

• Aliases are only valid within the scope of the query.
• The alias cannot be the same as the actual name of the table or column.
• If you use an alias to reference a column, you must use the alias in the WHERE clause, not the actual column name.

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