The SAP Data Services repository is a set of tables that hold user-created and predefined system objects, source and target metadata, and transformation rules. Set up repositories on an open client/server platform to facilitate sharing metadata with other enterprise tools.
https://blogs.sap.com/2015/12/27/sap-data-services-repositories-definition-and-configuration-part-1/#:~:text=The%20SAP%20Data%20Services%20repository,metadata%20with%20other%20enterprise%20tools.

There are four Audit Functions available in BODS.
* COUNT function helps to get the audit information on a table or output schema. The default datatype is INTEGER.
* SUM function helps to generate audit information like summation of measure type columns. E.g. Revenue. Accepted datatypes are INTEGER, DECIMAL, DOUBLE, REAL.
* AVERAGE function helps to generate audit information like average of measure type columns. E.g. Profit Margin. Accepted datatypes are INTEGER, DECIMAL, DOUBLE, REAL.
* CHECKSUM function helps to audit based on the hash values generated for VARCHAR datatype columns. The order of rows is important for the result of CHECKSUM function.
https://blogs.sap.com/2013/09/18/auditing-in-sap-data-services/