Why is this an issue?
Deprecated system tables and views are those that have been retained temporarily for backward compatibility, but which will eventually be removed
from the language. In effect, deprecation announces a grace period to allow the smooth transition from the old features to the new ones.
This rule raises an issue when system tables or views are used. Catalog tables and views should be used instead.
Noncompliant code example
SELECT name FROM syscolumns -- Noncompliant
SELECT name FROM sys.columns