funcA function to evaluateLazyExpr (required)
nameThe global name of this cache (needed when more than one)string
keyCache key to use.string (required)
periodThe latest age of the cache.int64


Creates a cache object.

A Cache is a data structure which is used to speed up calculating data by keeping it’s value in memory. A cache is essentially a key value store - when the key is accessed, the function will be calculated producing a value. If the key is accessed again, the value is returned from the cache without calculating it again.

For example consider the following:

    LET get_pid_query(Lpid) =
       SELECT Pid, Ppid, Name FROM pslist(pid=Lpid)

    SELECT cache(func=get_pid_query(Lpid=Pid), key=str(str=Pid))
    FROM ....

The cache will ensure that get_pid_query() is only called once per unique Pid by comparing the key against the internal memory store.

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