几种常用游标写法

创建表

CREATE TABLE "SCOTT"."DEPT"  (

    "DEPTNO" NUMBER(2,0),
    "DNAME"  VARCHAR2(14 BYTE),
    "LOC"    VARCHAR2(13 BYTE),
    CONSTRAINT "PK_DEPT" PRIMARY KEY ("DEPTNO") USING INDEX PCTFREE 10 INITRANS 2 MAXTRANS 255 COMPUTE STATISTICS STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645 PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT) TABLESPACE "USERS" ENABLE
  )
  PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255 NOCOMPRESS LOGGING STORAGE
  (
    INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645 PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT
  )
  TABLESPACE "USERS" ;

三种方式的游标展现：

SET serveroutput ON ;
DECLARE
  v_dname dept.dname%type;
  v_deptno dept.deptno%type;
  v_log dept.loc%type;
  CURSOR c_cursor(dno number)
  IS
    SELECT d.deptno, d.dname,d.loc FROM dept d where d.deptno = dno;
  type t_cursor IS ref CURSOR;
  v_cursor t_cursor;
  BEGIN
    dbms_output.put_line('使用游标一');
    BEGIN
      OPEN v_cursor FOR SELECT d.deptno,
      d.dname,d.loc FROM dept d ;
      LOOP
        FETCH v_cursor INTO v_deptno,v_log,v_dname;
      EXIT
    WHEN v_cursor%notfound ;
      dbms_output.put_line(v_deptno||'的名称是'||v_dname||v_log);
    END LOOP;
    CLOSE v_cursor;
  END ;
  dbms_output.put_line('使用游标二');
  BEGIN
    OPEN c_cursor(10);
    LOOP
      FETCH c_cursor INTO v_deptno,v_dname,v_log ;
      EXIT
    WHEN c_cursor%notfound;
      dbms_output.put_line(v_deptno||':'||v_dname);
    END LOOP ;
    CLOSE c_cursor;
  END ;
  dbms_output.put_line('使用游标三');
  BEGIN
    FOR cur IN c_cursor(10)
    LOOP
      dbms_output.put_line(cur.deptno || cur.dname);
    END LOOP;
  END;
END ;