Typed nils in Go 2

Re:Typed nils in Go 2 by marcus_holmes on Friday August 11, 2017 @02:43AM (#14987167)

I think they're referring to outer-joined tables.

SELECT a.id, b.name FROM a LEFT JOIN b ON a.id = b.id

If you get a NULL in the name field, you don't know if that's because there's no record in b for that id, or if there is a record in b for that id but it has a NULL name value. Sometimes that difference will be important.

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Re:Typed nils in Go 2 by sorkin2 on Friday August 11, 2017 @06:22AM (#14988160)

While admittedly this could be seen as a mistake in SQL, you can differentiate by looking at whether b.id is NULL or not.

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Re:Typed nils in Go 2 by marcus_holmes on Friday August 11, 2017 @08:44AM (#14989051)

true, but that's not the point the OP was making, I think :)

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