1. A method for detecting workload changes processed by a database management system, the method comprising: monitoring, by one or more computer processors, a plurality of workloads processed by the database management system in a first monitoring interval and a second monitoring interval, wherein monitoring the plurality of workloads comprises: retrieving, by the one or more computer processors, one or more access plans for the first and the second monitoring intervals from a statement cache; processing, by the one or more computer processors, the one or more access plans for the first and the second monitoring intervals to create one or more access plan hash codes, wherein the one or more access plan hash codes are hash codes of the one or more access plans for the first and the second monitoring intervals, wherein the access plan hash codes reduce workload; detecting, by the one or more computer processors, a change in a type of workload for the first and second monitoring interval; responsive to detecting the change in the type of workload for the first and second monitoring interval, identifying, by the one or more computer processors, the type of workload in the second monitoring interval based, at least in part, on one or more time invariant metrics; and updating, by the one or more computer processors, an entry in a library to include information pertinent to the identified type of workload.