steps for droping and recreating RI:-

1. genrate RI by using db2look:
db2look -d dbname -e -a -td @ -l -o dbname.sql

2.check the RI
select tbname, relname, refkeyname from sysibm.sysrels

create script for droping RI
select ‘ALTER TABLE ‘||tbname||’  DROP CONSTRAINT ‘||relname   from sysibm.sysrels your operation data migration/ db2move ..etc

4. recreate RI (keep only RI part in dbname.sql delete the rest)
db2 -td@ -vf dbname.sql