optional field

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1

Imported from previous forum

2

Sorry i have looked through the docs and the forum but still am not clear on what optional is supposed to mean.

If, for example, I have non optional string copy I cache the value and in the event that the presence map has zero against this field I used the cached value.

Is there a difference for a non-optional field? Eg should I have no cache for a non optional field and set the value to zero/blank when the presence map has zero against this field.

3

William,

FAST supports optional fields to efficiently support optional fields at the application level. FAST allows you to express using a NULL representation if a field is present from an application perspective. This is unrelated to the physical presence or absence due to field operator optimizations.

/Rolf

Sorry i have looked through the docs and the forum but still am not
clear on what optional is supposed to mean.

If, for example, I have non optional string copy I cache the value and
in the event that the presence map has zero against this field I used
the cached value.

Is there a difference for a non-optional field? Eg should I have no
cache for a non optional field and set the value to zero/blank when the
presence map has zero against this field.

4

Thnaks I see. The copy and increment operators work the same way for optional and mandatory fields. If the bit is set a new value is sent and the dictionary (or cache) updated. If not set the dictionary value is used.

Only for the default operator is there a difference between optional and mandatory values.

5

Thnaks I see. The copy and increment operators work the same way for optional and mandatory fields. If the bit is set a new value is sent and the dictionary (or cache) updated. If not set the dictionary value is used.

Only for the default operator is there a difference between optional and mandatory values.

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