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Given the following relationsTRAIN (NAME, START, DEST)TICKET (PNRNO., START, DEST, FARE) PASSENGER (NAME, ADDRESS, PNRNO.) Write SQL expressions for the following queries: Note: Assume NAME of Train is a column of Ticket.(i) List the names of passengers who are travelling from the begin to the destination station of the train.(ii) List the names of passengers who have a return journey ticket.(iii) Insert a new Shatabti train from Delhi to Bangalore.(iv) Cancel the ticket of Tintin.
(i) SELECT P.NAME FROM TRAIN T, TICKET I, PASSENGER P WHERE P.PNRNO = I.PNRNO AND T.NAME = I.NAME AND T.START = I.START AND T.DEST = I.DEST (ii) SELECT NAME FROM PASSENGER WHERE PNRNO IN (SELECT DISTINCT A.PNRNO FROM TICKET A, TICKET B WHERE A.PNRNO = B.PNRNO AND A.START = B.DEST AND A.DEST = B.START) (iii) INSERT INTO TRAIN VALUES(‘Shatabdi', ‘Delhi', ‘Banglore' (iv) DELETE FROM TICKET WHERE PNRNO = (SELECT PNRNO FROM PASSENGER WHERE NAME = ‘Tintin')
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Removing a Synonym: DROP SYNONYM D30;
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