How to select the next value from the sequence?
select xxxx.nextval from dual;
where XXXX is your sequence name.
NEXTVAL is a function used in oracle to get the next value of the sequence.
No current value exists for the sequence until the Oracle NEXVAL function has been called at least once.
A sequence is a database object, Which helps in generating a unique value(integer).
One sequence can serve multiple users to generate a unique value.
Sequences can be used to generate primary key values automatically as well.