I'm working on identifying and possibly cleaning up old and apparently unused objects. I created a table of library system objects using the QSYLOBJA API. Among the attributes I retrieved are the object change date and the object last-used date. For some database table and physical files, when I combine the object attribute data with data from the SYSTABLESTAT catalog view, I am seeing some things that don't make sense. All of the oddities involve objects with a last-used date that is null. Some database file objects that have an object change date prior to the last system IPL (and a null last-used date) show database activity from SYSTABLESTAT, e.g. open, close, logical and physical reads. How can there be database activity on the file without that changing the last-used date for the object? Some other database file objects have a change date subsequent to the last IPL, but no database activity (opens, closes, inserts, deletes, updates, logical and physical reads are all zero.) Again, last-used date is null. What could change the file object that doesn't update the last-used date?
On 16-Sep-2016 19:03 -0600, Jonathan Ball wrote: > <<SNIP>> > Some other database file objects have a change date subsequent to > the last IPL, but no database activity (opens, closes, inserts, > deletes, updates, logical and physical reads are all zero.) Again, > last-used date is null. What could change the file object that > doesn't update the last-used date? Not all "change" operations are related to I\O. For example, if the authority of a database file (*FILE) object is changed, then all members and the file object are all /changed/ and the last-change-date is updated; similarly, any /generic/ database file activity such as rename, move, alter, change-owner, et al. IIRC, only an open with a successful close will update the last-used date for a member, and some limited amount of reflection of the usage information is reflected in the file for each member; i.e. for specific details, the drill-down to the members is required, because the file-level details are not maintained or calculated as a cumulative of the information from all members. -- Regards, Chuck