Getting Accurate MARC Record Counts in Metadb

MARC _ _ t table issue: Multiple srs IDs associated with same instance ID

In the Metadb reporting database, the folio_source_record.marc__t table should have a unique srs_id associated with each instance ID. However, in early November 2025, the Reporting Team noticed that, for some records (which now varies daily from zero to thousands), there were multiple srs_ids associated with each instance_HRID. The multiples were older versions of the marc record, which normally would not appear in that table. The marc__t table should include only records where the state of the record is 'ACTUAL,' but it is including records where the state field is 'OLD.' So in queries that use the marc__t table, we are getting duplicate counts in those cases where the marc record has been updated and the old versions not purged. This issue came up before with LDP software, and it was fixed. There is code to address this issue for the Metadb software, but it is not clear that the code is working correctly. The Reporting Team is working with Index Data to address this problem.

Using 'ACTUAL' for Accurate Record Counts

In the meantime, you can use the record state of 'ACTUAL' as a workaround to make sure you are getting accurate record counts when you are using the folio_source_record.marc__t table.

Sample 1:

FROM folio_derived.instance_ext AS instext
LEFT JOIN folio_source_record.marc__t AS sm ON instext.instance_id = sm.instance_id
LEFT JOIN folio_source_record.records_lb AS rec ON sm.instance_id = rec.external_id
WHERE rec.state = 'ACTUAL' 

Here is an examples of a query that uses 'ACTUAL' :

https://github.com/cul-it/cul-folio-analytics/tree/main/metadb/canned_reports/MCR413

Here is an example of a query that shows two srs_id records that correspond to one instance record on the folio_source_record.marc _ _ t table along with the result. Note the join from the inventory table to the marc _ _ table. It isolates just one instance_hrid in the WHERE clause. The result shows one instance_hrid record associated with two srs_id records. One srs_id record shows a state of 'ACTUAL,' and the other shows a state of 'OLD'. This results in inflated record counts.

 
Sample 2:

SELECT DISTINCT
instance_ext.instance_hrid,
marc__t.instance_id,
marc__t.srs_id,
records_lb.state

FROM folio_derived.instance_ext
LEFT JOIN folio_source_record.marc__t
ON instance_ext.instance_id = marc__t.instance_id

LEFT JOIN folio_source_record.records_lb
ON marc__t.instance_id = records_lb.external_id
AND marc__t.srs_id = records_lb.id

WHERE instance_ext.instance_hrid = '11023049'

Result:

And if we wanted to show the WHERE condition “records_lb.state = ‘ACTUAL’ “ we could add it onto the same query as follows. Using 'ACTUAL' in the WHERE clause results in one srs_id associated with one instance_hrid. The count of records is no longer inflated.

Sample 3: