Joining the data between multiple table records

See more:

SQL

server

Hello every budy. I am developing an windows application..
i have a query like

Select estdate as date,SUM(netamt) as total from estimate_first group by estdate union select ivdate,SUM(netamt) from invoice_first group by ivdate
Select DATE,SUM(totalAmount) from stock_update_first group by Date

i want to make a single select query for both of the queries i have tried joins but not get desired please solved ..i want a single table for both of the queries...