Re: Trigger to create string to inverse SQL statement

maybe somebody wrote SP to invert update statement?

Best,
Jacek

2018-03-08 13:51 GMT+01:00 Łukasz Jarych <jaryszek(at)gmail(dot)com>:

> thank you,
>
> what do you mean use external program to build inverted queries. Do you
> have any examples?
>
> Best,
> Jacek
>
> 2018-03-08 13:44 GMT+01:00 Francisco Olarte <folarte(at)peoplecall(dot)com>:
>
>> Hello:
>>
>> On Thu, Mar 8, 2018 at 1:32 PM, Łukasz Jarych <jaryszek(at)gmail(dot)com> wrote:
>>
>>>
>>>
>>> i have a trigger which is added log history:
>>>
>>>
>>>
>>>
>> ​I'll trust it is, but I cannot really see any thing in there, it may be
>> better if in the future you used something like psql and pasted the data in
>> a text format, which people with no-so-good eyesight like me can zoom in.​
>>
>>
>>
>>> It is possible to create additional column here with string with
>>> inversed SQL statement?
>>>
>>> So in this case: "Delete FROM t_trig WHERE ID=1".
>>>
>>> And what i want is to have possibility to loop through table and execute
>>> inversed sql statement for each row.
>>>
>>
>> ​It should be. For inserts it is not that difficult, for updates YMMV, it
>> is difficult to ​reverse a command exactly, but you get new and old values
>> so you could write it. For deletes just reinsert. But I doubt there is a
>> function which does it for you, you'll have to code something, and I
>> suspect it may be easier to just capture op, old and new in your triggers
>> and use an external program to build the inverted queries.
>>
>> ​Francisco Olarte.​
>>
>>
>