I have a large SQL query that includes multiple Common Table Expressions (CTEs) and joins across various tables, totaling approximately 2,500 lines. I want to ensure that if any part of the query or a specific CTE fails—due to a missing table or column—the entire workflow or query does not fail. Instead, I would like a mechanism to handle such failures by automatically substituting any missing attributes (columns) with NULL values. This would allow the query to continue executing without interruption.

How can I achieve this, and are there best practices for implementing a fail-safe mechanism for such a large and complex query?