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Given the schema:

Depositor=(C-name,Account-no) and 3 relations more(not useful in this context),the tuple relational query for: "All customers having a loan or account at the bank" should be: {t|∃t∈Customer(∃s∈Borrower(t[C-name]=s[C-name])∨∃u∈Depositor(t[C-name]=u[C-name]))}

But in the answer: {t|∃s∈Borrower(t[C-name]=s[C-name])∨∃u∈Depositor(t[C-name]=u[C-name])}

Is this answer wrong and my thought answer correct?

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