Group/sub-group is a hierarchical way of grouping cached items. Let’s say, a cache has a large amount of product information. These products range from products like beverages, grocery to electronics etc. Among these products, there are further divisions like in electronic section group; there can be sub groups of home appliances, computer system gadgets, photography gadgets etc. Group is a logical partition of data; this partition can have a sub division (sub group) or can be just a major division (group), it is a two level grouping. Groups do not overlap but sub groups can be the same in one or more groups.
Case Sensitive: Group and sub group identifiers are case sensitive.
Retrieve/Remove using Groups: Using groups, all the items belonging to a particular group can be fetched or removed. The user can fetch just the keys and then only fetch a subset of them. Addition, update, removal, retrieval can be performed by specifying group identifier and/or its sub group identifier. Group keys or group data can be fetched using GetGroupKeys and GetGroupData API respectively.
Multiple Sub-Groups: NCache supports multiple sub groups within one group. But cache operations cannot be performed only with a sub group identifier, as two different groups can have the same sub group identifier.
Group Identifier cannot be Updated: Group identifier cannot be updated. For its update, cache key must first be removed and then inserted with a new group identifier.
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