What is the impact of not "closing" queries, when using the%Resultset library?

Question

Question

VICTOR GALVAO · Sep 15, 2020

Hi guys!!

In the system that I work, I came across an iterator pattern that uses the %Resultset library without performing the close after executing the query. Does anyone know how to say what are the impacts of not performing such a procedure?

If you have any model of iterator pattern made in caché to recommend as a good example, I will be grateful hehe :D

Discussion (5)0

Log in or sign up to continue

Robert Cemper Sep 15, 2020 to VICTOR GALVAO

If there are queries hanging around then the mayor impact is just on IRISTEMP or CACHETEMP database that might grow.
But it's not worth mentioning just for a query.

2 0

score 1 · Answer 1 · 2020-09-15T15:51:19-04:00

Typically a %ResultSet is an object. It is destroyed as soon as you de-reference it.
This could be a ba killing the referencing variable or by assigning a different value.
there is no need for a %Close or an object destructor. this happens implicitely.

set rs= ##class(%ResultSet).%New()
. . . . ; work it 
kill rs
; or 
set rs=""

score 0 · Answer 2 · 2020-09-15T16:54:14-04:00

Thanks for your help, Robert. But in the scenery when the object is not killed, and N queries are keeping open, what this can causes? An Opened query consumes memory and buffer? Wich impacts it causes on other processes? Do you know?

score 1 · Answer 3 · 2020-09-15T21:29:13-04:00

I agree with Robert. I have seldom if ever seen code that calls the ResultSet Close() method. There may be temprary globals left over in the CacheTemp database but if I am not mistaken there is a system Purge method that is run as part of the standard system tasks to clear-down these temporary structures. However if you want to complete the ResultSet functionality from Start to Finish then there is no harm in calling the Close() method.

score 0 · Answer 4 · 2020-09-15T21:29:24-04:00

I agree with Robert. I have seldom if ever seen code that calls the ResultSet Close() method. There may be temprary globals left over in the CacheTemp database but if I am not mistaken there is a system Purge method that is run as part of the standard system tasks to clear-down these temporary structures. However if you want to complete the ResultSet functionality from Start to Finish then there is no harm in calling the Close() method.