Re: proposal: schema PL session variables

On Tue, Feb 9, 2016 at 2:55 PM, David G. Johnston <
david(dot)g(dot)johnston(at)gmail(dot)com> wrote:

> On Tue, Feb 9, 2016 at 11:32 AM, Corey Huinker <corey(dot)huinker(at)gmail(dot)com>
> wrote:
>
>>
>> Oh, and I suggest we call them SESSION variables rather than SCHEMA
>> variables, to reinforce the idea of how long the values in the variables
>> live. A session variable is in a sense a 1x1 temp table, whose definition
>> persists across sessions but whose value does not.
>>
>> Of course, if they do persist across sessions, then yeah, SCHEMA makes
>> more sense. But every package variable in Oracle PL/SQL was initialized
>> when the package was first loaded into the session.
>>
>>
> ​The key distinction for SCHEMA was that all functions in the schema would
> be able to see them (and only those in the schema).
>
> I am a bit partial, with little deep thought, to the IMPORT mechanic.
> Changing them to actual session variables would be doable and you could
> allow for the IMPORT specification to use search_path or explicit means to
> locate said variables regardless of which schema​
>
> ​they exist in.
>
> However, part of the goal is to blend into the broader database community
> and thus increase porting capabilities. I'm not sure how well this would
> help fulfill that goal.
>
>
We're not going to get source compatibility without implementing packages,
and there's no enthusiasm for that. It's been stated a few times before by
some that the only value they see in packages is the package/session
variables. Pavel's idea gives us that.

I forgot to mention that if we're FROM-phobic the syntax could also be

IMPORT my_schema.bar AS g_localtext IN OUT text

Either way, you get the idea: the function defines what external globals
it's willing to see, and gives an alias for them, and it's the same
regardless of what the function language is.