The cache of a view can be invalidated using the
ALTER VQL sentence
(see section Modifying a Derived View).
There are two types of cache invalidation:
- “Full” invalidation, which removes all the cached data for a view.
- “Partial” invalidation that only removes the cached data that verifies a specified condition.
Both invalidation types support the
CASCADE option, which causes the
operation to propagate to the views participating in the definition of
the view specified in the invalidation sentence.
The next sentence would invalidate the cache for the
and for all the views participating in the
ALTER VIEW sampleView CACHE INVALIDATE ON CASCADE;
The next sentence is a partial invalidation. Only the tuples matching
with the specified condition will be invalidated. In this case, the
CASCADE option is not used and, therefore, the sentence will affect
sampleView view only:
ALTER VIEW sampleView CACHE INVALIDATE WHERE field1 = 'value';
The cache of views with “Full” cache cannot be invalidated on cascade. In addition, if you invalidate on cascade the cache of a view, the cache of the subviews whose cache mode is “Full”, will not be invalidated.
The stored procedure
CACHE_CONTENT returns information about the
contents of the cache. The section CACHE_CONTENT provides more
details about this procedure, its syntax and the information it returns.