fixed race condition causing incorrect IDs to be reported on INSERT

[bitmage]

When sending multiple INSERT operations to the MSSQL driver asynchronously, sometimes the IDs are incorrectly reported. I have observed 1) all the IDs being the same, 2) some IDs misreported, others correct. This is because MsSQL.prototype.create contains two SQL commands, the sum of which is not atomic. This change makes them atomic by wrapping them in a transaction.

Correct results are really important here - this was causing my foreign-key relationships to be configured incorrectly, which is a loss of data integrity.

I don't see a strong rationale for testing this, as it would be difficult to replicate, and would introduce indeterminacy into your test suite.

[slnode]

Can one of the admins verify this patch? To accept patch and trigger a build add comment ".ok\W+to\W+test."

[bitmage]

Yes, that looks much cleaner. I have updated the code - it will now produce SQL that looks like this:

INSERT INTO [dbo].[City] ([name],[type],[county])
OUTPUT INSERTED.id AS insertId
VALUES ((?),(?),(?));

Also note I am using the idName() function to calculate the ID field, so this should be compatible with customizations.

[bitmage]

@raymondfeng Sorry, I think it deleted your comment when I rebased.

[raymondfeng]

That's weird :-). Racing condition on github?