[tarantool-patches] Re: [PATCH 2/2] sql: compute resulting collation for concatenation

[Kirill Yukhin]

Hello,
On 17 Jan 16:33, Konstantin Osipov wrote:
> * Nikita Pettik <korablev at tarantool.org> [19/01/16 17:06]:
> > According to ANSI, result of concatenation operation should derive
> > collation sequence from its operands. Now it is not true: result is
> > always comes with no ("none") collation.
> 
> Generally, it should be very cheap to introduce expression static
> analysis phase by adding static analysis state to struct Expr.
> Yes, it's a blasphemy from separation of concerns point of view
> but it seems to be a lesser evil than invoking partial static
> analysis here and there during code generation.

I think that static analysis pass is of course very useful, but
it is big volume of work. I propose to move this effort to the next
release and adopt proposed solution.

--
Regards, Kirill Yukhin