Create Sequence in SQL Oracle, Create Trigger on Insert and Update in Oracle

Sequence in Oracle SQL. Following is the basic code to create a sequence in Oracle SQL

CREATE SEQUENCE sequence_name
START WITH 1
INCREMENT BY 1
MAXVALUE 99999999
MINVALUE 1
NOCYCLE;

Trigger on insert and update on any table 

Following code can be used to create a trigger on any table, It will invoke and do what you want when any value will get inserted and update in table

create or replace trigger trigger_name before insert OR update on table
for each row begin

write you logic here what should happen when trigger gets invoke.
end;