Re: proposal: session server side variables

2016-12-26 19:13 GMT+01:00 Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com>:

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> 2016-12-26 18:20 GMT+01:00 Fabien COELHO <coelho(at)cri(dot)ensmp(dot)fr>:
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>> And how would it interact with some "fully persistent/shared" variables?
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>> I have not any use case for this. I don't know about any similar feature
>> in other database systems. Oracle uses dbms_pipe or dbms_alert for
>> interprocess communication.
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>> I am thinking so it is possible to implement. If it is not ACID, then it
>> can work as custom statistic counters. If it should be ACID? Then is better
>> to use table. What I know, now is preferred share nothing design in
>> parallel systems - so for me, it looks like little bit dangerous feature -
>> and I see only one use case - custom statistics - where possible race
>> condition is not hard issue.
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>> But I don't plan to implement it in first stage. There should be strong
>> use case for implementing any complex feature in shared memory. But any
>> implementation doesn't breaking to implement it in feature.
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for custom statistic some extension based on bg worker can be better -
sharing variables are risk of race conditions - and developers are people
only.

I have not a clean opinion about this - the implementation should not be
hard, but I am not sure if this gun I would to give to users.

Regards

Pavel

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>> Regards
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>> Pavel
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>> --
>> Fabien.
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