SQL & PL/SQL

Hi,

I need to create a synonym that maps to two table under it, and more over it should map to the table which is most recently populated.

let me make it more clear. I have two table_1 and table_2,and there should be synonym table on the top of these tables.The table_1 gets populated on 1st week of each month and table_2 gets populated on 2nd week of each month. After the table_2 gets populated the table_1 would be truncated and this goes in cyclic ordering. Now i have to create a synonym the changes the mapping each time when one of this table gets populated.

any idea's would be appreciated

Thanks