On 7 March 2011 23:43, Robert Haas <robertmhaas@gmail.com> wrote:
> On Mon, Mar 7, 2011 at 12:59 PM, Thom Brown <thom@linux.com> wrote:
>> On 7 March 2011 22:39, Robert Haas <robertmhaas@gmail.com> wrote:
>>> On Mon, Mar 7, 2011 at 7:05 AM, Thom Brown <thom@linux.com> wrote:
>>>> This was spotted by someone who sent in a doc comment, although didn't
>>>> go with their suggestion. Patch attached.
>>>
>>> That's not really a typo so much as a think-o, I think. Maybe a
>>> little more text would help clarify: A column-specific trigger (one
>>> defined using the <literal>UPDATE OF
>>> <replaceable>column_name</replaceable></literal> syntax) will fire
>>> when...
>>>
>>> I think it would also be worth modifying this page so that the
>>> definition of event is in the syntax synopsis.
>>>
>>> Right now:
>>>
>>> rhaas=# \h create trigger
>>> Command: CREATE TRIGGER
>>> Description: define a new trigger
>>> Syntax:
>>> CREATE [ CONSTRAINT ] TRIGGER name { BEFORE | AFTER | INSTEAD OF } {
>>> event [ OR ... ] }
>>> ON table
>>> [ FROM referenced_table_name ]
>>> { NOT DEFERRABLE | [ DEFERRABLE ] { INITIALLY IMMEDIATE |
>>> INITIALLY DEFERRED } }
>>> [ FOR [ EACH ] { ROW | STATEMENT } ]
>>> [ WHEN ( condition ) ]
>>> EXECUTE PROCEDURE function_name ( arguments )
>>>
>>> It should really go on to say... "where event can be one of...", like
>>> EXPLAIN and COPY do, shouldn't it? Otherwise it's pretty hard to tell
>>> what you should put there without looking up the main docs.
>>
>> Yes, absolutely. In fact that's what I was looking for when I first
>> visited that page.
>>
>> So it would look like this:
>>
>> where event can be one of:
>>
>> INSERT [ OF column ]
>> UPDATE [ OF column ]
>> DELETE [ OF column ]
>> TRUNCATE
>
> Well, the existing documentation says that OF column is only allowed for UPDATE.
*copy/paste fail* Yes, utterly meaningless for INSERT/DELETE.
--
Thom Brown
Twitter: @darkixion
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