Another Look at MySQL 5.1's SQL Diagnostic Tools

No matter what they say, I don’t think it’s true. Database ‘experts’ say that 80-90% of a database’s overall performance comes from the SQL code that’s running against it. And I just don’t buy it. Instead, I think that most of a database’s performance comes from optimal design, and after that SQL code comes next. If you properly design your database, then you’re way ahead of the game in terms of performance issues. That’s when well-written SQL code can glide along your design like butter on a hot skillet.

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