WHILE循环语句在PL/SQL编程语言，只要给定的条件为真，则执行目标语句多次。
| WHILE condition LOOP |
| sequence_of_statements |
| END LOOP; |
| DECLARE |
| a number(2) := 10; |
| BEGIN |
| WHILE a < 20 LOOP |
| dbms_output.put_line('value of a: ' || a); |
| a := a + 1; |
| END LOOP; |
| END; |
| / |
value of a: 10 value of a: 11 value of a: 12 value of a: 13 value of a: 14 value of a: 15 value of a: 16 value of a: 17 value of a: 18 value of a: 19 PL/SQL procedure successfully completed.
