not to MERGE some fields

rperseguini

Hello,

We're changing our real-time quote streaming to Lightstreamer.

My problem:
Some fields that belong to this minute can't be merged with same fields of the next minute.
When the minute changes, current state of these fields must be delivered to clients.

Any idea of how to do this ?

Is there any kind of control over the MERGE operation ?

What is the preprocessor ? Are there any docs about it ?

We're afraid of changing from MERGE to DISTINCT mode and fall into bandwidth problems.

thanks in advance.

Giuseppe Corti

Hi rperseguini,

If I understood your scenario correctly you could switch to the COMMAND subscription mode.
The trick to adopt in your Data Adapter is to consider as "key" field for COMMAND mode updates the 1-minute slot. Please consider that in COMMAND mode updates for the same key are handled as MERGE.
Furthermore your Data Adapter should take care of push an ADD command when the new 1-minute slot starts and also to consider the maximum number of slots to manage with the possibility of deleting the oldest ones.

For demo example of COMMAND mode please refer to this: https://demos.lightstreamer.com/PortfolioDemo_Basic/

I don't think the Preprocessor is useful in your case, however you can find the documentation in section 3.4 of General Concepts documentation.

Regards,
Giuseppe