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Bit Manipulation in SQL Server 2022

Itzik Ben-Gan twiddles some bits:

The need to manipulate data at the bit level with bitwise operations isn’t common in T-SQL, but you might stumble into such a need in some specialized scenarios. Some implementations store a set of flags (yes/no, on/off, true/false) in a single integer or binary-typed column, where each bit represents a different flag. One example is using a bitwise representation of a set of user/role permissions. Another example is using a bitwise representation of a set of settings turned on or off in a given environment. Even SQL Server stores some flag-based data using bitwise representation.

Here’s the deal. I don’t mind that this new syntax exists, particularly because—as Itzik points out—there are areas built into SQL Server which use integers to store bit flags. In application code, however, this gets a sharp “No!” from me in any code review. If you need to decompose values in your table as a matter of course, your table is not in first normal form. Having a table not be in 1NF isn’t the end of the world but at that point, I think the onus is on the developer to defend the violation at that point.

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