On 2019-08-16 14:50, Rich Shepard wrote:
On Fri, 16 Aug 2019, Charles Clavadetscher wrote:
Another way to keep a history is using a daterange instead of two
columns for start and end date. Something like
create table labor_rate_mult (
rate real primary_key,
validity daterange not null
)
Charles,
Just out of curiosity, what is the range for a rate that is still
current?
Does it change every day?
Regards,
Rich
Hi Rich
That would be a range with an empty upper bound. Let's say that the rate
is valid since 2019-08-14 then the range would look like
[2019-08-14,)
A query to find the current rate would look like:
SELECT rate
FROM labor_rate_mult
WHERE validity @> CURRENT_DATE;
Here you can find documentation on the range types (cool stuff I
believe):
https://www.postgresql.org/docs/11/rangetypes.html
Regards
Charles
--
Charles Clavadetscher
Swiss PostgreSQL Users Group
Treasurer
Neugasse 84
CH – 8005 Zürich
http://www.swisspug.org
+---------------------------+
| ____ ______ ___ |
| / )/ \/ \ |
| ( / __ _\ ) |
| \ (/ o) ( o) ) |
| \_ (_ ) \ ) _/ |
| \ /\_/ \)/ |
| \/ <//| |\\> |
| _| | |
| \|_/ |
| |
| Swiss PostgreSQL |
| Users Group |
| |
+---------------------------+
