尝试声明游标时出现此错误

Question

正在尝试创建游标来计算所有国家/地区的印刷量并遇到这些错误

Answer 1

• %rowtyBe?
• fetch 应该以 semi-colon
结束
• when 子句没有 =
• exit 子句应紧跟在 fetch
之后

因此，对于示例数据

SQL> SELECT * FROM countries;

COUNTRY_ID COUNTRY  REGION_ID
---------- ------- ----------
         1 Croatia          1
         2 Austria          1
         3 Germany          2

SQL> SET SERVEROUTPUT ON

那个 PL/SQL 块可能看起来像这样：

SQL> DECLARE
  2     CURSOR cur_country IS
  3        SELECT country_id, country_name, region_id
  4          FROM countries
  5         WHERE region_id = 1;
  6
  7     v_ctr_record  cur_country%ROWTYPE;
  8  BEGIN
  9     OPEN cur_country;
 10
 11     LOOP
 12        FETCH cur_country INTO v_ctr_record;
 13
 14        EXIT WHEN cur_country%NOTFOUND;
 15
 16        DBMS_OUTPUT.put_line (
 17              'Country name '
 18           || v_ctr_record.country_name
 19           || ' country_id '
 20           || v_ctr_record.country_id
 21           || ' Region id '
 22           || v_ctr_record.region_id);
 23     END LOOP;
 24
 25     CLOSE cur_country;
 26  END;
 27  /
Country name Croatia country_id 1 Region id 1
Country name Austria country_id 2 Region id 1

PL/SQL procedure successfully completed.

SQL>

---

或者，切换到游标FOR循环；使用起来更简单：

SQL> BEGIN
  2     FOR v_ctr_record IN (SELECT country_id, country_name, region_id
  3                            FROM countries
  4                           WHERE region_id = 1)
  5     LOOP
  6        DBMS_OUTPUT.put_line (
  7              'Country name '
  8           || v_ctr_record.country_name
  9           || ' country_id '
 10           || v_ctr_record.country_id
 11           || ' Region id '
 12           || v_ctr_record.region_id);
 13     END LOOP;
 14  END;
 15  /
Country name Croatia country_id 1 Region id 1
Country name Austria country_id 2 Region id 1

PL/SQL procedure successfully completed.

SQL>