https://www.oracle.com/technology/pub/articles/vasiliev-php-dcn.html
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As is well known, caching the results of database queries can dramatically improve script execution time and minimize the load on the database server. This technique can be especially effective if the data you are dealing with is quite static. This is because many data requests to a remote database may be eventually satisfied from the local cache, thus avoiding the need to make a connection to the database, execute the query, and fetch the results.
