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If 5 relations are put through the zig-zag configuration of join tree and the order of join does not matter, how many different join trees are possible?

1. 960
 
2. 840
 
3. 1024
 
4. 512
in Databases 307 views

1 Answer

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960. we can use this formula n!(2power n-2).
0
can u explain this formula how has it come?

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