data dates from different sources, create mastercalendar

[#1]

hi guys,

I have different sources in my qvw and my intention is, how to get the all the dates data into the mastercalendar ?

because 1 source is from qvd, the other from excel, and some frome database sql..

If I join the dates, so I get a too big file.

How can I "join" them effective?

thanks much !