Re: multi-tenant issues with stored procedures

"MIDRANGE-L" <midrange-l-bounces@xxxxxxxxxxxx> wrote on 11/27/2017
05:22:46 PM:

However, I've been told that we've had problems in the past with

external

apps calling (external) stored procedures when the library list needs to
change between calls.

This is my first experience with multi-tenancy, but I know so of you on

the

list have the same architecture.


Key points, the library list change affects not just the data library

but

the program library also (as our customers may be on different versions
)

I think in the past, what we've tried is
my_sp ext stored proc for myrpgpgm

Where my_sp is defined in a global library and myrpgpgm is supposed to

be

called from a version specific library (using the library list)

I'm curious as to how others deal with multi-tenancy.

Also I suppose, I'd like to find out more about when external stored
procedures are resolved and more importantly re-resolved?

We deal with it by first making sure that the off-platform call is
made with Naming Convention *SYS in place. This insures that both the job
and SQL will honor the library list that is in place (for both files and
programs). To accomplish this the off-platform connection string must
contain 'naming=system' (sans quotes). If using an ODBC DSN, make sure
the Server tab displays "System naming convention (*SYS)" in the Naming
convention drop-down box.

For the second step, we have a method in place which allows us to
switch between "tenants" without having to log out and back in. We
extended this to our stored procedures by passing a "tenant" id as the
first parameter and call QCMDEXC to execute the same switching process
that would be used for an interactive session. What this switching
process does is to replace the current job's library list based on the
initial library list found in a job description that corresponds to the
"tenant" id. We use the QWDRJOBD API to extract the library list from the
job description and the QLICHGLL API to apply that library list to the
current job.

The only issue that might remain is files left open from the
previous "tenant".

Sincerely,

Dave Clark