Non-equi-join is a join using non-equality binary relational operator such as (<, ≤, ≠, >, ≥) . Also known as a Non-equi Theta-Join. Theta join combines tuples from different relations provided they satisfy the theta condition. General form of theta-join can use use all kinds of comparison operators (<, ≤, =, ≠, >, ≥) Both equi-join (join using = operator) and non-equi-join are subsets of general form on Theta-join.
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