DF070: Not aliased table sources are used in the query.

Last modified: June 12, 2025

The topic describes the DF070 T-SQL code analysis rule.

Category

BEST PRACTICE

Message

Not aliased table sources are used in the query.

Description

Always use aliases for table sources in queries to improve readability and avoid ambiguity, especially in complex queries or joins.

Additional information

Aliasing table sources in T-SQL means assigning a short name (alias) to a table or view referenced in a query. This practice helps make complex queries easier to read and maintain, especially when working with multiple tables or when the same table appears more than once (as in self-joins or subqueries).

Noncompliant code example

-- it is not clear to which table column belongs
SELECT name, code
FROM dbo.Parent INNER JOIN dbo.Child ON Id = ParentId
GO

Compliant solution

SELECT p.name, c.code
FROM dbo.Parent p INNER JOIN dbo.Child c ON p.Id = c.ParentId
GO