CREATE OR REPLACE FUNCTION csharp.migrate_call_numbers(source_ou INT, dest_ou INT) RETURNS INT AS $func$
DECLARE
    source_org  actor.org_unit%ROWTYPE;
    dest_org    actor.org_unit%ROWTYPE;
    source_cn   asset.call_number%ROWTYPE;
    target_cn   asset.call_number%ROWTYPE;
    hold        action.hold_request%ROWTYPE;

BEGIN

    SELECT INTO source_org *
        FROM actor.org_unit
        WHERE id = source_ou;

    SELECT INTO dest_org *
        FROM actor.org_unit
        WHERE id = dest_ou;

    -- Find call numbers attached to the source org ...
    FOR source_cn IN
        SELECT *
            FROM asset.call_number
            WHERE owning_lib = source_org.id
            AND NOT deleted
    LOOP

    SELECT INTO target_cn *
        FROM  asset.call_number
        WHERE label = source_cn.label
        AND prefix = source_cn.prefix
        AND suffix = source_cn.suffix
        AND owning_lib = dest_org.id
        AND record = source_cn.record
        AND NOT deleted;

    -- ... and if there's a conflicting one on the target ...
    IF FOUND THEN

            -- ... move the copies to that, and ...
            UPDATE  asset.copy
              SET   call_number = target_cn.id
              WHERE call_number = source_cn.id;

            -- ... move V holds to the move-target call number
            FOR hold IN SELECT * FROM action.hold_request WHERE target = source_cn.id AND hold_type = 'V' LOOP

                    UPDATE  action.hold_request
                      SET   target = target_cn.id
                      WHERE id = hold.id;

            END LOOP;

            UPDATE asset.call_number SET deleted = TRUE WHERE id = source_cn.id;

    -- ... if not ...
    ELSE
            -- ... just move the call number to the target org
            UPDATE  asset.call_number
              SET   owning_lib = dest_org.id
              WHERE id = source_cn.id;
    END IF;
    END LOOP;
    RETURN 1;
END;
$func$ LANGUAGE plpgsql;