T-SQL += started in 2008?!

A few days ago, The Impatient DBA wrote that in Microsoft SQL Server 2008, MS added an old C operator: +=.  Simply put, add a value to a variable.  You can run the following code that he provided:

DECLARE @shamwow int = 0;
SET @shamwow += 1;
SET @shamwow += 1;
SELECT @shamwow AS ShamWow;

And @shamwow is now 2.  Without using the += operator, we’d be doing @shamwow = @shamwow +1.  Is += better?  It is certainly shorter, but I think that’s mainly a matter of personal choice.  If you code in other languages that support it, I think it would probably be a good thing.

But there’s more than just adding: there’s also operators for the other basic math functions: -=, *=, /=.  Let’s continue playing with @shamwow with the following code:

DECLARE @shamwow FLOAT = 3;

SET @shamwow *= 3;

SELECT @shamwow;

SET @shamwow /= 2;

SELECT @shamwow;

SET @shamwow -= 3;

SELECT @shamwow;

SSMS will return 9, 4.5, and 1.5.

Pretty cool, eh?

But there’s two problems.  First, this is supported in T-SQL, but not in Access 2013 VBA.  The other is that there’s another pair of C operators, ++ and — (that’s minus minus, not an em dash).  Add or subtract one from the preceding variable, so you’d do set @shamwow++ if it were supported.  And these latter two are not supported in either T-SQL or VBA.  I’m sure they’re alive and well in C# and probably several other .Net languages.

I’m frankly amazed that this happened EIGHT YEARS AGO and I haven’t seen it in common usage.  It’s been in C for probably as long as there has been C, and now we have it in T-SQL.  Something about new tricks and old dogs comes to mind.


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