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Why does this SQL subquery run a thousand times? #sqldebugging

Why does this SQL subquery run a thousand times in production. The SQL code uses a correlated subquery in SELECT. In MySQL it executes once per row. In SQL one query can become millions of executions.

Видео Why does this SQL subquery run a thousand times? #sqldebugging канала PrecisionSQL
sql analytics sql bug sql code review sql correlated subquery sql data integrity sql database sql debugging sql engineering sql join sql n+1 sql performance sql production bug sql reliability sql scaling whats wrong with this sql query
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11 марта 2026 г. 22:15:13
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