Creating a Sequence in PL/SQL

A sequence specifies a unique value. This one will give us the number 1 the first time we use it. Then it will give us 2 then 3 etc.. if for some reason the order gets messed up it will skip 20 numbers then give us the next number in the sequence.

CREATE SEQUENCE CustomerID_SEQ
INCREMENT BY 1
START WITH 1
MINVALUE 1
MAXVALUE 9999999999
NOCYCLE
NOORDER
CACHE 20;

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