PgAmin view

On Thursday, October 26, 2023, Shaozhong SHI <shishaozhong@gmail.com> wrote:

If a PgAmin view is created and tables it queries are missing, what will
happen?

If a PdAmin view is created, and it may take 20 hours to complete, what
will happen?

Would views automatically run, when you start the PgAmin?

Test it with a view that takes seconds to run.

David J.

On 10/26/23 03:56, Shaozhong SHI wrote:

If a PgAmin view is created and tables it queries are missing, what will
happen?

Easy enough to test:

create view test_vw as select * from non_existent_table;
ERROR: relation "non_existent_table" does not exist
LINE 1: create view test_vw as select * from non_existent_table;

If a PdAmin view is created, and it may take 20 hours to complete, what
will happen?

Docs:

https://www.postgresql.org/docs/current/sql-createview.html

"CREATE VIEW defines a view of a query. The view is not physically
materialized. Instead, the query is run every time the view is
referenced in a query."

Would views automatically run, when you start the PgAmin?

See above. The view query will not execute until specifically asked for
and nothing I have seen in my limited use of pgAdmin does that
automatically.

Regards,

David

--
Adrian Klaver
adrian.klaver@aklaver.com

On Thu, Oct 26, 2023 at 5:56 AM Shaozhong SHI <shishaozhong@gmail.com>
wrote:

If a PgAmin view is created and tables it queries are missing, what will
happen?

If a PdAmin view is created, and it may take 20 hours to complete, what
will happen?

Would views automatically run, when you start the PgAmin?

Views are rewritten into the query when the query is planned.

merlin