give backcolor to some row of gridview according to db

Question

Theare 2 tables in datatbase of same column name.There are 10 records in first table and same 8 records in second table.

I display 10 records in gridview now i want to give backcolor to those two recods which are not in second table.

How can i use sql query  and give backcolor to those 2 records.

 

 for all records i use following query-

 

"select id,amount,DATE from OT

union

select id,amount,DATE from CH"

 

for backcolor purpose i have following query-

 

"select id,amount,DATE from OT where id not in (select id from CH )"

 

Please help me.