#DCL Statement

DCL Statement为静态SQL执行语句。

# COMMIT|ROLLBACK

COMMIT/ROLLBACK只能使用缺省的COMMIT/ROLLBACK语法,不能为其指定任何选项。

示例

CREATE OR REPLACE PROCEDURE ya_proc IS
no VARCHAR(10);
name VARCHAR(20);
str1 VARCHAR(100) := 'select area_no,area_name from area where area_no=:a';
BEGIN
  
  
EXECUTE IMMEDIATE str1 INTO no,name USING '03';       --动态SQL
DBMS_OUTPUT.PUT_LINE('区域号码:'||no||'区域名称:'||name);
  
UPDATE area SET area_no='00' WHERE area_no='03';    --静态SQL
COMMIT;        --静态SQL
  
EXECUTE IMMEDIATE str1 INTO no,name USING '03' ;       --动态SQL,由于执行UPDATE语句,此语句将无结果返回
DBMS_OUTPUT.PUT_LINE('区域号码:'||no||'区域名称:'||name);
END;
/
   
exec ya_proc;
   
--result
区域号码:03区域名称:华南
[9:1]YAS-05206 no data found

# SAVEPOINT

SAVEPOINT的语法形式为:

BEGIN
SAVEPOINT savepoint_name;
...
ROLLBACK TO savepoint_name;
...
END;

示例

--程序捕获到ZERO_DIVIDE异常,执行rollback,之前插入到area表的数据被回滚,所以第二次执行str1语句时抛出未找到数据的异常
DECLARE
a INT := 0;
b INT := 1;
c INT;
no VARCHAR(10);
name VARCHAR(20);
str1 VARCHAR(100) := 'select area_no,area_name from area where area_no=''99''';
BEGIN
SAVEPOINT start_trans;
c := 2;
INSERT INTO area VALUES('99','other',DEFAULT);
EXECUTE IMMEDIATE str1 INTO no,name ;
DBMS_OUTPUT.PUT_LINE('区域号码:'||no||'区域名称:'||name);
c := b/a;
EXCEPTION
WHEN ZERO_DIVIDE THEN
ROLLBACK TO start_trans;
EXECUTE IMMEDIATE str1 INTO no,name ;
DBMS_OUTPUT.PUT_LINE('区域号码:'||no||'区域名称:'||name);
END;
/
 
--result
区域号码:99区域名称:other
[18:1]YAS-05206 no data found
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