Carrying Baggage Through Query Plans: Why Wide Queries Get Heavy

I see this pattern repeatedly: a “wide” query that returns many columns and less than 100k rows runs slowly. SQL Server gets slow when it drags large amounts of baggage through the entire query plan, like a solo traveler struggling with massive suitcases in an airport instead of picking them up close to their destination.

SQL Server often minimizes data access by grabbing all the columns it needs early in query execution, then doing joins and filters. This means presentation columns get picked up early.

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