Explaining Implicit Conversion

Monica Rathbun explains to us what implicit conversion is and when it can go wrong:

Another quick post of simple changes you can make to your code to create more optimal execution plans. This one is on implicit conversions. An implicit conversion is when SQL Server must automatically convert a data type from one type to another when comparing values, moving data or combining values with other values. When these values are converted, during the query process, it adds additional overhead and impacts performance.

Read on for more info, including a common scenario where implicit conversion causes performance degradation.

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