oracle存储过程中的select与参数详细说明
create or replace procedure pro_test
is
begin
select * from t_test;
end pro_test;
这个正确吗?
昨天因为这个,耽误了好久(在一个存储过程中用了select语句,但既没有用游标也没有用into).
在存储过程(oracle)中如果用了select语句,要么使用"select into 变量"语句要么使用游标,oracle不支持单独的select语句(如表述有误请指出).
select into 比较简单,但是如果返回的是一个结果集就无法满足要求了.
游标分cursor型游标和sys_refcursor型游标两种
cursor型游标--不能用于参数传递
create or replace procedure pro_test() is
cusor_1 cursor is select 字段名 from 表名 where 条件;
(或者
select class_name into cursor_2 from class where ...;
cursor的另一种用法,需要写在begin和end之间)
begin
select class_name into cursor_2 from class where ...;
可以使用
for xxx in cursor
loop
....
end loop; --对cursor进行遍历
end pro_test;
sys_refcursor型游标
create or replace procedure pro_test(rscursor out sys_refcursor) is
cursor sys_refcursor;
name varhcar(20);
begin
open cursor for
select name from student where ...; --使用open来打开进行赋值
--遍历
loop
fetch cursor into name --fetch into来打开遍历的每条数据
exit when cursor%notfound; --未找到记录信息
dbms_output.putline(xxxx);
end loop;
rscursor := cursor;
end pro_test;
如何在存储过程中调用其他的存储过程(这些都是带参数的)
一个带参数的存储过程。
sql> create or replace procedure helloworld1 (
2 p_user_name varchar2
3 ) as
4 begin
5 dbms_output.put_line('hello ' || p_user_name || '!');
6 end helloworld1;
7 /procedure created.
sql> create or replace procedure callhelloworld1 (
2 p_user varchar2
3 ) as
4 begin
5 -- 调用存储过程的 存储过程
6 helloworld1(p_user);
7 end callhelloworld1;
8 /procedure created.
执行
sql> set serveroutput on
sql> exec callhelloworld1( 'tom' );
hello tom!pl/sql procedure successfully completed.

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