Re: poll: CHECK TRIGGER? - Mailing list pgsql-hackers

From Heikki Linnakangas
Subject Re: poll: CHECK TRIGGER?
Date
Msg-id 4F7488A6.8030900@enterprisedb.com
Whole thread Raw
In response to Re: poll: CHECK TRIGGER?  (Pavel Stehule <pavel.stehule@gmail.com>)
Responses Re: poll: CHECK TRIGGER?  (Pavel Stehule <pavel.stehule@gmail.com>)
List pgsql-hackers
On 28.03.2012 23:54, Pavel Stehule wrote:
> 2012/3/28 Heikki Linnakangas<heikki.linnakangas@enterprisedb.com>:
>> In prepare_expr(), you use a subtransaction to catch any ERRORs that happen
>> during parsing the expression. That's a good idea, and I think many of the
>> check_* functions could be greatly simplified by adopting a similar
>> approach. Just ereport() any errors you find, and catch them at the
>> appropriate level, appending the error to the output string. Your current
>> approach of returning true/false depending on whether there was any errors
>> seems tedious.
>
> This is not possible, when we would to enable "fatal_errors = false"
> checking. I can do subtransaction in prepare_expr, because it is the
> most deep level, but I cannot to use it elsewhere, because I cannot
> handle exception and continue with other parts of statement.

Well, you can continue on the next statement. That's almost as good. In 
practice, if there's one error in a statement, it seems unlikely that 
you would correctly diagnose other errors on the same line. They're more 
likely to be fallout of the same mistake.

--   Heikki Linnakangas  EnterpriseDB   http://www.enterprisedb.com


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