Re: proposal: plpgsql - Assert statement

On 9/5/14 10:09 AM, Pavel Stehule wrote:
>> I think this could still be parsed correctly, though I'm not 100% sure on
>> that:
>>
>> ASSERT WARNING (EXISTS(SELECT ..)), 'data are there';
>>
>
> PLpgSQL uses a ';' or some plpgsql keyword as SQL statement delimiter. It
> reason why RETURN QUERY ... ';' So in this case can practical to place SQL
> statement on the end of plpgsql statement.

*shrug*  There are lots of cases where a comma is used as well, e.g. 
RAISE NOTICE '..', <expr>, <expr>;

> parenthesis are not practical, because it is hard to identify bug ..

I don't see why.  The PL/PgSQL SQL parser goes to great lengths to 
identify unmatched parenthesis.  But the parens probably aren't 
necessary in the first place; you could just omit them and keep parsing 
until the next comma AFAICT.  So the syntax would be:

RAISE [ NOTICE | WARNING | EXCEPTION/ASSERT/WHATEVER ]
boolean_expr [, error_message [, error_message_param [, ... ] ] ];

> A simplicity of integration SQL and PLpgSQL is in using "smart" keywords -
> It is more verbose, and it allow to well diagnostics

I disagree.  The new keywords provide nothing of value here.  They even 
encourage the use of quirky syntax in *exchange* for verbosity ("IS NOT 
NULL pk"? really?).


.marko