Collection and reorganization schemata specify how long data assigned to this schema (see Assigning Collection and Reorganization Schemata to Performance Values) is to be stored in the Central Performance History (CPH) with which resolution.
Use these expert settings if the normal screen for maintaining collection and reorganization schemata (see Maintaining Collection and Reorganization Schemata (Standard Setting)) does not meet your needs.
In the CPH, you can define in great detail which performance values you want to store from which systems in which resolution, and for how long. This number of configuration settings is, however, only necessary for a very small number of users, as SAP already delivers powerful standard schemata.
The expert setting, in which you can set all parameters of the schemata as you wish, is described here. The prerequisites for using the expert setting are:
Creating a Collection and Reorganization Schema
Note that the time unit of the storage periods is the unit of the corresponding aggregate in each case. This means that different units apply for the different rows of the table.
Editing an Existing Collection and Reorganization Schema
Deleting a Collection and Reorganization Schema
Central Performance History of the Monitoring Architecture start page