I am new to using client server databases and I am unsure about opening and closing sessions.
The customer is not a large organization and there are less than twenty users in total.
There are multiple applications, some which the users have open almost all the time, and some that are opened only when needed.
Some applications are specifically for manipulating the data, others access the data only intermittently.
Is it best to open a session when the application opens, and then close it when the application closes, or should I open a session when the application needs to access the data, and close the session when the data access is completed?
Should I be doing this differently if the application accesses the data in almost every function, compared to an application that access the data only intermittently?

On 12/23/2020 11:57 PM, bpolky wrote:
> Is it best to open a session when the application opens, and then close it when the application closes, or should I open a session when the application needs to access the data, and close the session when the data access is completed?

There are no absolute rules here but some notes below.

First of all make sure you follow these guidelines if you are dealing
with threading at all  :
https://www.elevatesoft.com/manual?action=viewtopic&id=edb2&product=rsdelphiwin32&version=10.4&topic=Multi_Threaded_Applications

Otherwise IMHO it depends on few factors including your app design and
whether you use databound UI controls and such.

For example do you use default session for main UI thread or do you
create your own ?

Do you use transactions ?

Are different app sections related at all or are they all relatively
independent - in terms of data access and need to track changes across.

Finally remote sessions can have hiccups - things like brief network
outage or somebody putting computer to sleep etc - so you still need to
deal with making sure connection is actually still alive and re-connecting.

I have used one session for main UI thread and for forms with databound
controls. This session is opened by first form using data and forms can
just call global class to manage this (open/re-open) and you can also
deal with various sessions events from single point.

If code just needs to process something then creating a separate session
at that time might be easier since you can handle everything in single
block of code - for example errors when connecting session - and then
close the session when done.

Raul