SA0119 : Consider aliasing all table sources in the query

It’s common practice to alias table sources in the FROM clause of SELECT, UPDATE, and DELETE statements. Not using aliases can lead to confusion and make the SQL code harder to read and maintain, especially in complex queries with multiple tables.

For example:

1-- Example of a query missing table aliases
2SELECT FirstName, LastName FROM Employees
3JOIN Departments ON Employees.DepartmentID = Departments.DepartmentID;

This query does not use aliases, which can cause confusion, especially when multiple tables have similar column names or when queries grow in complexity. Best practices suggest using aliases to improve query readability and manageability.

• Lack of aliases can make it difficult to track which columns belong to which table, increasing the chance of errors.

• Using aliases can improve performance by making query plans more efficient and easier to optimize.

Improve the readability and maintainability of SQL code by aliasing all table sources in your queries.

Follow these steps to address the issue:

1. Identify all tables used in your FROM clause within SELECT, UPDATE, and DELETE statements.

2. Assign an alias to each table. An alias is a shorthand reference that simplifies reading and writing queries. Use a meaningful alias for each table to make your SQL statements more intuitive.

3. Replace all explicit table names in your query with their corresponding aliases. Ensure consistency across the query to maintain clarity.

For example:

1-- Example of a corrected query using table aliases
2SELECT E.FirstName, E.LastName
3FROM Employees AS E
4JOIN Departments AS D ON E.DepartmentID = D.DepartmentID;

The rule has a Batch scope and is applied only on the SQL script.

The rule does not need Analysis Context or SQL Connection.

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