Date Correlation Optimization

Monica Rathbun explains another quasi-hidden SQL Server configuration option:

According to MSDN – The DATE_CORRELATION_OPTIMIZATION database SET option improves the performance of queries that perform an equi-join between two tables whose date or datetime columns are correlated, and which specify a date restriction in the query predicate.

How many of you read what MSDN says and thinks “wuuuuuttt, English please”? I do.

Read on for the English translation.

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