Concatenate Missing data from another table

[rupaliqlik]

Hello Team,

I have  2 table .

MDOID Is common  in both of them.
MDO->MDOID
AttendanceApproval->MDOID

If MDOID is present in MDO ,but not in AttendanceApproval then Approval_Status='Pending' and the MDOStatus 
should be blank.

How to check whether MDOID is available or not.

Thanks,

Rupali Ethape

@abhijitnalekar @sunny_talwar