질의 최적화 예제 선택연산과 추출 연산은 가급적 일찍 수행하라.
1200불을 초과하는 대출한 모든 고객의 이름을 찾아라 customer-name (amount>1200 (borrower.loan-number=loan.loan-number (borrower loan))) customer-name (borrower.loan-number=loan.loan-number (borrower (loan-number (amount>1200 ( loan)))))
Perryridge 지점에 대출이 있는 모든 고객의 이름을 찾아라. customer-name(branch-name=“Perryridge” (borrower.loan-number=loan.loan-number (borrower loan))) customer-name(borrower.loan-number=loan.loan-number (borrower (loan-number(branch-name=“Perryridge” (loan)))))
Downtown 지점에 예금계좌가 있는 모든 고객의 이름을 찾아라. customer-name(branch-name=“Downtown” (account.account-number=depositor.account-number (account depositor))) customer-name(account.account-number=depositor.account-number (depositor (account-number(branch-name=“Downtown” (account )))))