On 9/23/21 10:16 AM, Israel Brewster wrote:
On Sep 23, 2021, at 4:34 AM, Ryan Booz <r...@timescale.com
<mailto:r...@timescale.com>> wrote:
Heh, I honestly forgot about the recursive CTE. Certainly worth a try
and wouldn't require installing other extensions.
This is what depesz is referring to:
https://wiki.postgresql.org/wiki/Loose_indexscan
<https://wiki.postgresql.org/wiki/Loose_indexscan>
Thanks for the pointer. Will definitely have to spend some time
wrapping my brain around that one - I’ve done some CTE’s before, but
not recursive that I can recall. Should be fun!
If it helps matters any, my structure is currently the following:
table “stations” listing station details (name, latitude, longitude,
etc) with a smallint primary key “id"
table “data” with many (many!) data columns (mostly doubles), a
station column that is a smallint referencing the stations table, and
a channel column which is a varchar containing the *name* of the
channel the data came in on.
I will readily accept that this may not be the best structure for the
DB. For example, perhaps the channel column should be normalized out
as has been mentioned a couple of times as an option. This would make
sense, and would certainly simplify this portion of the project.
If I do go with a lookup table updated by a trigger, what would be the
best option for the query the trigger runs - an upset (ON CONFLICT DO
NOTHING)? Or a query followed by an insert if needed? The normal case
would be that the entry already exists (millions of hits vs only the
occasional insert needed).
I would look into pre-loading the lookup table (and pre-emptive
maintenance). Add the foreign key, but not the trigger.
