Differences

This shows you the differences between two versions of the page.

--- indexing:tracking_record_changes [2021/07/28 10:44] – [Enabling Change Tracking] demiankatz
+++ indexing:tracking_record_changes [2021/08/03 13:59] (current) – [More on OAI-PMH] demiankatz
@@ Line 61: / Line 61: @@
 For a general introduction to the OAI-PMH protocol, see [[http://www.oaforum.org/tutorial/|this tutorial]].
+==== Related Video ====
+For more on OAI-PMH, see the [[videos:oai-pmh_server_and_harvest_functionality|OAI-PMH Server and Harvest Functionality]] video.
 ===== Enhanced RSS Functionality =====
@@ Line 73: / Line 75: @@
 By default, VuFind tries to use the ILS driver to power the "new items" search. However, not all ILS drivers support this functionality. If you turn on record change tracking, you can modify the method setting to "solr" in the [NewItem] section of [[configuration:files:searches.ini|searches.ini]] to gain new item searches without an ILS dependency.
+===== Frequently Asked Questions =====
+This section contains answers to frequently asked questions about the technical details of the change-tracking implementation.
+==== If I reindex my existing records, will VuFind think that they are new? ====
+No, the change tracking system will only update dates in its internal database if it encounters a record ID it has never seen before, or if the record itself has changed. If you index the same MARC file over and over again, that record will only be recorded in the database once. However, if you edit the MARC record and export a new version, when you index the changed record, VuFind will update the "last indexed" value to reflect that something is different.
+This behavior is dependent on records containing last-changed dates. In the case of MARC records, VuFind checks the 005 and 008 fields for modification dates. Note that if no dates are found, VuFind will always assume that the record has changed as a precaution; thus, it is important to ensure that your ILS is including one of these fields in exported records if you want reliable change tracking. In the case of XSLT records, the custom PHP methods used by the XSLT expect a modification date parameter, and you should be sure to extract it from an appropriate place in your XML to ensure consistent behavior.
+==== What happens when records are deleted? ====
+If you remove records from your ILS, you should inform VuFind about the deleted records so it can update its change tracking database. This enables the system to correctly report deleted records through OAI-PMH, and it also allows the system to treat records as new if they later are added again after being previously deleted. You can use the util/deletes [[administration:command_line_utilities|command line utility]] for this purpose.
+For systems that have no easy way of reporting deleted records, a common solution is to simply delete VuFind's index, and then reindex from a fresh full export. If you do this, the deleted records will be removed from VuFind's index correctly, so normal search behavior will work as expected. However, the change tracking system will not be aware that records have been removed, and the now-missing records will not be reported as deleted through OAI-PMH (or any other feature that might rely on delete tracking functionality). This may or may not be a problem for you, depending on your use case.
 ---- struct data ----
+properties.Page Owner :
 ----