If id is null, use the value from sequence

If id is null, use the value from sequence
 
SQL> create table myTable(
  2 id number primary key,
  3 blob_content blob
  4 )
  5 /

Table created.

SQL>
SQL> create sequence myTable_seq
  2 /

Sequence created.

SQL>
SQL> create or replace trigger biu_myTable
  2 before insert or update on myTable
  3 for each row
  4 begin
  5 if :new.id is null then
  6 select myTable_seq.nextval into :new.id from dual;
  7 end if;
  8 end;
  9 /

Trigger created.

SQL> drop table myTable;

Table dropped.

SQL> drop sequence myTable_seq;

Sequence dropped.




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