Sorry for being "Captain Obvious" -
If you use this method, just remember to have the necessary storage
capacity available for two versions of the table in question.
Med venlig hilsen / Kind regards
Bo Victor Thomsen
Den 04-08-2022 kl. 01:18 skrev Scott Ribe:
On Aug 3, 2022, at 5:06 PM, Thomaz Luiz Santos <thomaz.santos@xxxxxxxxx> wrote:
I have one question: is it possible to minimize the downtime for this process ( because this table is large. ), using another strategy, like one view and updating the view ?
Yes, using a view and redefining it after the new data is loaded would work. You could also:
- load new data into a new table
- begin transaction
- drop old table
- rename new table
- commit
The drop/rename dance executes very quickly because it's just manipulating catalog entries--with the caveat that dropping the table requires an exclusive lock for the obvious reason, so if you have a long-running transaction using that table, you can wind up waiting for it.
Look at the docs for CREATE TABLE and the "LIKE" option, which gives you a shortcut to creating a table with the structure of an existing one.
One peculiarity you might or might not care about: when you create your indexes on the new table, they will be named based on that table's name, and when you rename it the indexes don't get renamed. Personally, I am OK with "my_table_temp_some_idx" on "my_table", but if this offends your sensibilities, you can always rename the indexes ;-) and constraints ;-)
