[Info-vax] RDB, trigger, native procedure and ActiveMQ

[Arne Vajhøj]

On 5/31/2021 6:10 PM, Jan-Erik Söderholm wrote:
> Den 2021-05-31 kl. 21:49, skrev Arne Vajhøj:
>> On 5/31/2021 6:36 AM, Jan-Erik Söderholm wrote:
>>> Den 2021-05-31 kl. 01:47, skrev Arne Vajhøj:
>>>> Rdb features have been discussed here a few times and
>>>> some time ago I read a bit in the Rdb manual and found
>>>> the section on native procedure.
>>>>
>>>> And since I like playing around with such stuff I
>>>> created a little demo.
>>>>
>>>> Setup:
>>>>
>>>> Rdb table -> insert trigger -> procedure written in C -> STOMP 
>>>> library -> message queue on ActiveMQ
>>
>>> Was it the "database clients" that did the table insert?
>>
>> Yes.
>>
>>> If so, it would work from any source, it doesn't matter *how* the
>>> record was inserted into the table, the trigger would fire anyway.
>>
>> Yes.
>>
>> That is the whole point. Any program can insert the data and
>> trigger the send to message queue. And any program can read
>> from the message queue and take action.
> 
> OK, fine... :-)
> But then I do not see the point in listing three "database clients".
> It is simply not relevant.

I could have picked any number of database clients and picked
any database clients. I picked those 3 as being illustrative
because they are so different.

There is a point in having multiple database clients. If there were
only one and that application was one that could be modified, then
that application could have send to the message queue instead
of relying on the database to send to the message queue.

Arne