Re: proposal: plpgsql - Assert statement

2014-09-09 7:54 GMT+02:00 Craig Ringer <craig(at)2ndquadrant(dot)com>:

> On 09/05/2014 05:21 PM, Pavel Stehule wrote:
> >
> > *shrug* Doing it in SQL would probably break more stuff. I'm trying to
> > contain the damage. And arguably, this is mostly only useful in
> PL/PgSQL.
>
> I've wanted assertions in SQL enough that I often write trivial wrappers
> around `raise` in PL/PgSQL for use in `CASE` statements etc.
>

In this moment we have no agreement on syntax, but there was not defined a
requirements for aggregations. I looked on assertions in some languages and
implementation and design of assertions is really varied.

I though about it, and "Assertions" is not plpgsql only issue. It must be
supported by core, and by other PL.

There are two usual requests for Assertions:

a) Isn't possible handle a assertion exception anywhere .. it enforce
ROLLBACK in 100%

b) Assertions should be disabled globally .. I am not sure, it it is a good
idea, but I can understand so some tests based on queries to data can be
performance issue.

Important question is a relation assertations and exceptions. Is it only
shortcut for exception or some different?

Comments?

Regards

Pavel

>
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> Craig Ringer http://www.2ndQuadrant.com/
> PostgreSQL Development, 24x7 Support, Training & Services
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