Arithmetic With NULL

Kevin Feasel

2016-04-27

T-SQL

Kennie Nybo Pontoppidan looks at how NULL values complicate arithmetic operations:

If NULL is used in an in-row expression, the full expression will be NULL. This makes sense for most arithmetic operations, because NULL means unknown.

Here is an example with NULL plus/minus ONE:

There’s a consistency to NULL operations, but it’s sometimes a weird consistency.

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