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Chapter 46: Sequence




        Examples



        Create Sequence


          CREATE SEQUENCE orders_seq
          START WITH     1000
          INCREMENT BY   1;


        Creates a sequence with a starting value of 1000 which is incremented by 1.

        Using Sequences


        a reference to seq_name.NEXTVAL is used to get the next value in a sequence. A single
        statement can only generate a single sequence value. If there are multiple references to
        NEXTVAL in a statement, they use will use the same generated number.


        NEXTVAL can be used for INSERTS


         INSERT INTO Orders (Order_UID, Customer)
                 VALUES (orders_seq.NEXTVAL, 1032);


        It can be used for UPDATES


         UPDATE Orders
         SET Order_UID = orders_seq.NEXTVAL
         WHERE Customer = 581;


        It can also be used for SELECTS


         SELECT Order_seq.NEXTVAL FROM dual;


        Read Sequence online: https://riptutorial.com/sql/topic/1586/sequence



























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