exception_failure.sql

pl/sql的综合运用上例用到的oracle里关于游标的几个内置函数:％isopen,％notfound,％rowcount。 隐式游标更多用在for loop中

SET serveroutput ON;

DECLARE 
	TYPE emp_record_type IS RECORD
		 (EMPNO NUMBER(4) NOT NULL :=1000,
		  ename VARCHAR2(10));	  
	CURSOR emp_cursor IS SELECT a.empno,a.ename FROM emp a;
	emp_record emp_record_type;
BEGIN
	 IF NOT emp_cursor%isopen THEN OPEN emp_cursor;
	 END IF;
	 LOOP
	 	 FETCH emp_cursor INTO emp_record;
		 	dbms_output.put_line(emp_record.empno);
	     EXIT WHEN emp_cursor%NOTFOUND; 
	 END LOOP;
	 CLOSE emp_cursor;
	 EXCEPTION 
	 	WHEN INVALID_CURSOR THEN
			 dbms_output.put_line('非法游标游走');
		WHEN OTHERS THEN
			 dbms_output.put_line('其它异常产生');
END;