Which tables does Service Desk use to link contacts and Configuration Items?
Service Desk contacts and Configuration Items are linked using the attribute "cenv" and the reference values are stored in Lrel_Table table. The following fields in the Lrel_Table store the reference information:
You need to update these fields in order to link the contacts and CIs in bulk.
You may also use the Web Services method createLrelRelationship() to create these relationships.