database - Associativity of natural join -


i wondering whether natural join operation in relational algebra associative. mean, following equation true?

(s1 natural join s2) natural join s3 = s1 natural join (s2 natural join s3)

it looks associative me intuitively, not sure.

thanks

an inner join returns rows match on condition. not have special treatment either right or left hand table. inner join associative.

a natural join inner join on columns same name. since inner join associative, natural join.


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