What is the difference in these two methods of determining NULL

I've got some T-SQL code that does a check to determine if a field is NULL. Normally I simply do a IS NULL check on the field, however in this code I've been given, the method used is WHERE ISNULL(MyField, '') <> ''

Is this a more accepted method? Is it better or worse than simply saying WHERE MyField IS NOT NULL

Cheers for your help

Answers


It accounts for both null fields and fields with an empty string. In some cases this is desired over just a null field.


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