create or replace procedure phone(v in out varchar2)
is
begin v:= '('||substr(v,1,3)||')'||sunstr(v,4,3)||'-'||substr(v,7);
end phone;

خطا بس في كتابه ال SUBSTR التانيه
كده صح

create or replace procedure phone(v in out varchar2)
is
begin v:= '(' || SUBSTR(v,1,3) || ')' || SUBSTR(v,4,3) || '-' || SUBSTR(v,7);
end phone;
/
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