Ripple fields

"Rippling" enables you to keep historical records by specifying a list of fields (for example those which detail the last five previously traded prices) and moving the value of each field on to the next FID when a new update arrives.

When an update arrives, existing values are shuffled one field to the right, and the new value goes into the first field in the ripple field list.

The example below shows values rippling across a ripple list of four fields: Field 1, Field 2, Field 3, and Field 4.

Field 1 Field 2 Field 3 Field 4

Update 1

12.3

Update 2

12.1

12.3

Update 3

12.5

12.1

12.3

Update 4

12.2

12.5

12.1

12.3

Update 5

12.6

12.2

12.5

12.1

If ripple-enable is set to true, then the TREP Adapter will use the ripple lists read from the TREP dictionary.

If the ripple fields are used from the dictionary then upa-priority-service should be configured to the Dictionary service ( upa-dictionary-service). This will disallow peer connections and requests until the dictionary service is up.

The version of the fields dictionary read by the TREP Adapter is logged in the event log.

If user-defined fields require rippling these should be added to the file ripple.conf. If ripple-enable is configured, then these ripples will be applied to the specified fields.


See also: