1. Anar Godjaev
http://anargodjaev.wordpress.com/
Conditional Control
if <condition> then
...
elsif conditions then
...
else
...
end if;
EX:
if upper(v_last_name) = 'GETZ' then
v_mgr := 102;
end if;
case
when
when
...
else
end;
selector
expression then result
expression then result
result
EX:
declare
v_grade char(1) := 'B';--upper(g_p_grade);
v_appraisal varchar2(20);
begin
v_appraisal :=
case v_grade
when 'A' then 'Excellent'
when 'B' then 'Very Good'
when 'C' then 'Good'
else 'No grade'
end;
dbms_output.put_line('grade ' || v_grade || ' apraisal ' ||v_appraisal);
end;
Loop:
Basic loop, for loop, while loop
Loop
...
Exit when condition;
End loop
While condition loop
...
End loop
For counter in [reverse] lower bound ... upper bound loop
End for
Cursors:
Declare -> open -> fetch -> if empty then -> close
Create cursor -> open it –> load the current row into variables -> test for empty -> close
EX:
declare

2. Anar Godjaev
http://anargodjaev.wordpress.com/
cursor emp_cursor is
select employee_id, last_name from employees;
cursor dept_cursor is
select * from departments where location_id=170;
begin
open emp_cursor;
open dept_cursor;
loop
exit when emp_cursor%NOTFOUND;
fetch emp_cursor into v_id , v_last;
end loop;
close emp_cursor;
close dept_cursor;
end;
Cursor Attributes:
<cursor_name>%ISOPEN
<cursor_name>%NOTFOUND
<cursor_name>%FOUND
<cursor_name>%ROWCOUNT
EX:
/**
SQL%ROWCOUNT number of rows affected by the most recent sql satement
SQL%FOUND returns true if the most recent sql statement affected any rows
SQL%NOTFOUND returns true if the most recent sql statement affected no rows
SQL%ISOPEN returns true if the cursor is open, if close then returns false
**/
declare
v_employee_id employees.employee_id%TYPE := 176;
rows_deleted varchar2(30);
begin
delete from employees where employee_id = v_eployee_id ;
rows_deleted := sql%ROWCOUNT || ' rows deleted';
dbms_output.put_line(rows_deleted);
end;
Cursor and Records:
EX:
declare
cursor emp_cursor is
select employee_id, last_name from employees;
emp_record emp_cursor%ROWTYPE;
begin
open emp_cursor;
loop
fetch emp_cursor into emp_record;
exit when emp_cursor%NOTFOUND;
insert into temp_list
(emp_id, emp_name)
values
(emp_Record.employee_id, emp_record.last_name);
end loop;
commit;

3. Anar Godjaev
http://anargodjaev.wordpress.com/
close emp_cursor;
end;
EX:
Declare
type cur_type is ref cursor;
c1 cur_type;
r1 v$datafile%ROWTYPE;
Begin
open c1 for select * from v$datafile;
loop
fetch c1 into r1;
exit when c1%NOTFOUND;
Dbms_output.put_line(r1.name);
end loop;
/*
For r1 in c1
Loop
Dbms_output.put_line(r1.name);
End loop;
*/
End;
Cursors with parameters:
EX:
declare
cursor emp_cursor (p_deptno number, p_job varchar2) is
select employee_id, last_name from employees
where department_id = p_deptno
and job_id = p_job;
begin
open emp_cursor (80,'sales_rep');
close emp_cursor;
open emp_cursor (60,'it_prog');
-- ..
end;
Exception Handling:
1- predefined oracle server error
2- non predefined oracle server error
3- user defined error
predefined oracle server errors:
no_data_found //single row select returned no data
too_many_rows //single row select returned more than one row
invalid_cursor //illegal cursor operation
zero_devide //attempted to devide by zero
dup_val_on_index //attempted to insert a duplicate value
cursor_already_open
invalid_number //convertion of char string to a number
login_denied
EX:
begin
--...

4. Anar Godjaev
http://anargodjaev.wordpress.com/
null;
exception
when no_data_found then
--...
null;
when too_many_rows then
--...
null;
end;
user defined oracle server errors:
EX:
declare
e_invalid_department exception;
begin
update departments set department_name = g_v_department_name
where department_id = g_v_department_number;
if sql%NOTFOUND then
raise e_invalid_department;
end if;
commit;
exception
when e_invalid_department then
dbms_output.put_line ('no such dept id ');
end;
EX:
delete from employees where manager_id = v_mngr;
if sql%NOTFOUND then
raise_application_error (-20202, 'not valid manager');
end if;
--OR
...
Exception
when no_data_found then
Raise_application_error ('no data found');
End;