--discover all the tables that use vendorid
SELECT table_name FROM INFORMATION_SCHEMA.columns WHERE COLUMN_NAME = 'vendorid' ORDER BY table_name
--finds all vendor records that do not have a current record in any of the work tables
--add to the LEFT JOINs to include all the tables that might have VENDORID in use.
SELECT v.*
FROM pm00200 v
LEFT JOIN (SELECT DISTINCT vendorid FROM pm10000) ptw ON ptw.VENDORID = v.VENDORID
LEFT JOIN (SELECT DISTINCT vendorid FROM pm20000) pto ON pto.VENDORID = v.VENDORID
LEFT JOIN (SELECT DISTINCT vendorid FROM pm30200) pth ON pth.VENDORID = v.VENDORID
LEFT JOIN (SELECT DISTINCT vendorid FROM pop10110) pol ON pol.VENDORID = v.VENDORID
LEFT JOIN (SELECT DISTINCT vendorid FROM pop30110) polh ON polh.VENDORID = v.VENDORID
WHERE ptw.VENDORID IS NULL
AND pto.VENDORID IS NULL
AND pth.VENDORID IS null
AND pol.VENDORID IS null
AND polh.VENDORID IS null
--once you're happy with the result set from the above query, this will change the Vendor Class of the selected vendors
--and from there they can be mass deleted (or so I'm told)
UPDATE pm00200 SET VNDCLSID = 'MY NEW CLASS'
FROM pm00200 v
LEFT JOIN (SELECT DISTINCT vendorid FROM pm10000) ptw ON ptw.VENDORID = v.VENDORID
LEFT JOIN (SELECT DISTINCT vendorid FROM pm20000) pto ON pto.VENDORID = v.VENDORID
LEFT JOIN (SELECT DISTINCT vendorid FROM pm30200) pth ON pth.VENDORID = v.VENDORID
LEFT JOIN (SELECT DISTINCT vendorid FROM pop10110) pol ON pol.VENDORID = v.VENDORID
LEFT JOIN (SELECT DISTINCT vendorid FROM pop30110) polh ON polh.VENDORID = v.VENDORID
WHERE ptw.VENDORID IS NULL
AND pto.VENDORID IS NULL
AND pth.VENDORID IS null
AND pol.VENDORID IS null
AND polh.VENDORID IS null