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SQL

Why EXISTS Beats COUNT(*) in Conditional Queries

- 24.01.26 - ErcanOPAK

You don’t need numbers when you only need truth.

IF EXISTS (
  SELECT 1 FROM Orders WHERE CustomerId = 42
)
BEGIN
  PRINT 'Has orders'
END

Why it’s faster

  • Stops at the first match

  • Avoids full scans

  • Reduces CPU usage

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"ORDER BY" with CASE and UNION in SQL Server

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Post Views: 6

Post navigation

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