R1&R3 will be combined ...but for R2
Let consider this example:-
X Y Z W
2 2 3 6
3 2 4 7
1 2 2 8
Now consider decomposition R2:-
Y Z
2 3
2 4
2 2
R1R3=R'
X Y W
2 2 6
3 2 7
1 2 8
now th3 natural join of R' and R2 wil give following relation:-
9 touples...not like the old table
therefor
Lossy decomposition
lossy..
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