WebSphere eXtreme Scale Product Overview > Cache concepts > Database integration



Sparse and complete cache


WebSphere eXtreme Scale can be used as a sparse cache or a complete cache. A sparse cache only keeps a subset of the total data, while a complete cache keeps all of the data. and can be populated lazily, on-demand. Sparse caches are normally accessed using keys (instead of indexes or queries) since the data is only partially available.

When a key is not present (a cache miss), the next tier is invoked and the data is fetched and inserted into the respective cache tier. If using a query or index, only the currently loaded values are accessed and the requests are not forwarded to the other tiers. A complete cache contains all of the required data and can be accessed using non-key attributes with indexes or queries.

A complete cache is preloaded with data prior to applications’ using it, and can effectively function as a database replacement. After data is loaded, it can be treated similarly to a database. Since all of the data is available, queries and indexes can be used to find and aggregate data.



Parent topic

Database integration


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