• Procedure cache is the old name for the plan cache.

    Plan cache - cache of compiled query plans so that the optimiser doesn't have to regenerate them

    Data cache - cache of data pages so that they don't have to be read off disk (slow) every single time they're needed.

    Gail Shaw
    Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
    SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability

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