Re: overriding current_timestamp

On Feb 23, 2012, at 3:08 AM, Peter Eisentraut wrote:

> For (unit) testing, I have often had the need to override the current
> timestamp in the database system. For example, a column default,
> function, or views would make use of the current timestamp in some way,
> and to test the behavior, it's sometimes useful to tweak the current
> timestamp.
>
> What might be a good way to do that?
>
> Just overwrite xactStartTimestamp? Is that safe? If it weren't static,
> a user-loaded function could do it.
>
> Overwrite pg_catalog.now() in the test database?
>
> Other ideas?
>
> Some semi-official support for this sort of thing would be good.

I create a "mock" schema, add the function to it, and then put it in the search_path ahead of pg_catalog. See the example starting at slide 48 on http://www.slideshare.net/justatheory/pgtap-best-practices.

Best,

David