Re: 回复：回复：A question about leakproof

On Mon, 2022-10-17 at 13:17 +0800, qiumingcheng wrote:
> > you seem to be imagining that changes in a query's plan on the basis of changes
> > in collected statistics have something to do with this.  They do not.
>
> Sorry, I may not fully understand what you mean. I mean that after my tests,
> the execution results of this SQL (explain select * from tb_a_date_v1) execution plan
> are different under different users, which is really related to the parameter proleakproof.

That's the idea behind leakproof: if a function is not leakproof, the optimizer
will not move it "inside" the view definition.  Then the function is evaluated only
after the view definition.  That may very well lead to a slower execution plan,
because it cannot use certain indexes on the underlying tables.

It is the price you have to pay for good security.

Yours,
Laurenz Albe