On 06/01/2013 06:47 AM, Kevin Grittner wrote:
> Adrian Klaver <adrian.klaver@gmail.com> wrote:
>> On 05/31/2013 08:15 AM, Kevin Grittner wrote:
>>> Adrian Klaver <adrian.klaver@gmail.com> wrote:
>>>> On 05/31/2013 06:32 AM, Kevin Grittner wrote:
>
>>>> But why? The OP specified FOR EACH ROW in the trigger
>>>> statement.
>>>
>
>> The thing is I thought it was working to spec and the docs would
>> seem to be saying it does:
>>
>> http://www.postgresql.org/docs/9.2/interactive/sql-createtrigger.html
>> "
>> FOR EACH ROW
>> FOR EACH STATEMENT
>> This specifies whether the trigger procedure should be fired once
>> for every row affected by the trigger event, or just once per SQL
>> statement. If neither is specified, FOR EACH STATEMENT is the
>> default. Constraint triggers can only be specified FOR EACH ROW."
>>
>> Now it is entirely possible I am reading the above wrong and if
>> that is the case I would welcome an explanation of where I am
>> misinterpreting it.
>
> Currently on an AFTER ... FOR EACH ROW we fire the trigger once
> *for* each affected row, that's true. But we don't do it
> immediately after the *triggering event* -- we do it immediately
> after the *data change statement*. The issue isn't how many times
> we execute the trigger, or with what parameters, but *when* it
> runs.
Aah, that was the part I was missing. So to see if I understand, in the
OPs case:
1) The first case worked as Juliano expected because the INSERTs where
done in a loop where each INSERT was a discrete statement and there was
a 1:1 correspondence between statement and triggering event.
2) The second case did not work as expected because the INSERTs where
wrapped up in a single statement and the AFTER triggers ran for each row
after all the rows where inserted not after each row was inserted.
--
Adrian Klaver
adrian.klaver@gmail.com
