On 4 November 2011 10:20, Miroslav Šimulčík
<simulcik.miro@gmail.com> wrote:
Hi.
I'm working on transactiontime temporal support for postgresql 9.0.4. Each original table with transactiontime support has associated history table, where original row is stored before each update or delete operation on it. Both original and history tables have internal timestamp columns for storing the period of validity of row versions. History tables are internal and I want to restrict any DML operation on it, so nobody can change history of operations made on original table. Problem is, that I don't know where to implement the mechanism for storing original rows to history tables. Rewrite rules are not suitable, because they are not working with inheritance and I can't use triggers, because inserts to history tables are restricted. Can you point me to place in postgresql backend where can i implement this and maybe give me some hints about how to do it correctly?
Thank you.
Best regards
Miroslav Simulcik
Hi,
use triggers with security definer so the owner of the triggers and the history table can insert into it, but normal user cannot - this user only is able to change data in original table, and triggers will copy the data, but will be executed using the first user credentials.
On the other hand: superuser always can delete data from a table, so you cannot stop him from doing that.
regards
Szymon
