Re: Really unique session ID - PID + connection timestamp?

Dear John!

This is not about MS.

This is about: how to get unique session_id. This could be "pid" + "client
starting time".
The pid isn't unique, where I can get "client's starting time"?

But I think the solution is pg_activity view.

There is no same PID as mine, because no one have same subprocess as mine.

So I can filter to my line. This contains my client's starting time.
Anybody's record had same PID in the past can be eliminated.
Other PID's are invalid if were not in it the view.

If Lock_Is_On(aTable, aIDValue, HisPID, HisClientStartTS):

p = GetMyPID

bCanUnlock = False
if p = HisPID:

// This is mine PID - but really mine?

ts = SelectClientStartTSFromActivityLog(p)

if ts = HisClientStartTS:

// It's mine

pass

else:

// The pid is same, but client's starting time is different - we can unlock
it, this is not mine

bCanUnlock = True

else:

// This is not mine PID, we can check for existence here

if HaveClientPIDAndStartTSinActivityLog(HisPID, HisTS) = False:

bCanUnlock = True // No one have it, he was off

if bCanUnlock:

RemoveTableLock(aTable, aID)

else:

raise Exception('Cannot lock the object because locked by another user!')

Thanks for your inspiration!

2016-04-09 12:30 GMT+02:00 John R Pierce <pierce(at)hogranch(dot)com>:

> On 4/9/2016 1:30 AM, Durumdara wrote:
>
>> In MS we had...
>>
>
> If you want Microsoft's unique version of SQL, run Microsoft SQL. That
> stuff you describe is a whole bunch of implementation specific wierdness
> from the standpoint of someone outside, looking in..
>
>
>
>
> --
> john r pierce, recycling bits in santa cruz
>
>
>
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