For UAE no need to cancel Qatar employment visa to stamp Qatar Visa. This rule is only in Saudi and Qatar(ie if you have other RP you need to cancel before stamping local RP). However it is better always to cancel the Qatar Visa or else you will have problem in case you need to travel to Qatar for business purposes.
In 2003 I moved to Bahrain without cancelling the visa and landed in trouble when I made a business visit to Qatar later. However there was no problem for me in Bahrain to stamp their visa like in UAE.
For UAE no need to cancel Qatar employment visa to stamp Qatar Visa. This rule is only in Saudi and Qatar(ie if you have other RP you need to cancel before stamping local RP). However it is better always to cancel the Qatar Visa or else you will have problem in case you need to travel to Qatar for business purposes.
In 2003 I moved to Bahrain without cancelling the visa and landed in trouble when I made a business visit to Qatar later. However there was no problem for me in Bahrain to stamp their visa like in UAE.
AJAY