yes you can do that...
in calculated column you write like this
Created.[Create order] .condition Resolved.[Resolced Order]
but I need to use the new date as the quick filter...
If datasource is same for two tables then before taking the data into Tableau you have to union these two tables by writing custom SQL. If datasource is different then it will not work. Only thing you can do is already suggested by Tableau Kumar (Appending values from other datasource). Data Blending will not work as you are going to merge two columns into a single one. If you OK with single selection then you can use parameter.