best practice using memcached with mysql search query?
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i've friendship_request database table , will if this table have say a million record
when i'll try to search for requests concerning tom for example and actually there is no friendship request for tom in these million record so which is better:
to index to in memcache when some one send request to tom and then first try to check memcache for tom so if present go to database and make a search query.
OR to make a search query directly without first check memcache
which is faster?
thanks