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Currently dbcc DATA_PURITY complains about subnormal real values in some of my columns, such as 7.561407E-42. I would rather keep them in my tables, and ask dbcc to ignore them.

I am OK with the check on upper limit, and other checks on other column types. So I would rather keep running the utility, but have it stop complaining about legitimate very low values.

Is there a way to accomplish that?

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The whole purpose of DBCC CHECKDB WITH DATA_PURITY is to check the database for column values that are not valid or are out-of-range.

In sql server 2000, it was possible to store out-of-range values in columns of certain datatypes like Float,real, datetime, etc. But moving from SQL 2005 and up, SQL Server will flag out those out-of-range values as it follows Single-precision floating-point format. Check @PaulWhite's answer here.

From BOL :

DBCC CHECKDB detects columns with date and time values that are larger than or less than the acceptable range for the datetime data type; or decimal or approximate-numeric data type columns with scale or precision values that are not valid.

You must fix those errors reported as described in KB923247.

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I think dbcc could do better - subnormal real values are valid. As such, they should not be considered out of range. – A-K Jan 27 '14 at 16:12
@AlexKuznetsov Seems like it as pointed out by PaulWhite. Also, agree that DBCC should not point out subnormal values as out-of-range. Also, the link that I referenced, you are the one who is the OP :-) – Kin Jan 27 '14 at 16:16

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