Oracle 存储过程
简要记录存储过程语法与Java程序的调用方式，
一 存储过程
首先，我们建立一个简单的表进行存储过程的测试
create table xuesheng(id integer , xing_ming varchar2 ( 25 ), yu_wen number , shu_xue number ); insert into xuesheng values ( 1 , ' zhangsan ' , 80 , 90 ) insert into xuesheng values ( 2 , ' lisi ' , 85 , 87 )1）无返回值的存储过程
2）有单个数据值返回的存储过程
create or replace procedure xs_proc(temp_name in varchar2 , temp_num out number ) is num_1 number ; num_2 number ; begin select yu_wen, shu_xue into num_1, num_2 from xuesheng where xing_ming = temp_name; -- dbms_output.put_line(num_1 + num_2); temp_num : = num_1 + num_2; end ;
其中，以上两种与sql server基本类似，而对于返回数据集时，上述方法则不能满足我们的要求。在Oracle中，一般使用ref cursor来返回数据集。示例代码如下：
3）有返回值的存储过程(列表返回)
首先，建立我们自己的包。并定义包中的一个自定义ref cursor
create or replace package mypackage as type my_cursor is ref cursor ; end mypackage;
在定义了ref cursor后，可以书写我们的程序代码
create or replace procedure xs_proc_list(shuxue in number , p_cursor out mypackage.my_cursor) is begin open p_cursor for select * from xuesheng where shu_xue > shuxue; end xs_proc_list;
在本节中，我们使用java语言调用存储过程。其中，关键是使用CallableStatement这个对象，代码如下：
String oracleDriverName = "oracle.jdbc.driver.OracleDriver";
// 以下使用的Test就是Oracle里的表空间
String oracleUrlToConnect = "jdbc:oracle:thin:@127.0.0.1:1521:orcl";
Connection myConnection = null;
try {
Class.forName(oracleDriverName);
} catch (ClassNotFoundException ex) {
ex.printStackTrace();
}
try {
myConnection = DriverManager.getConnection(oracleUrlToConnect,
"xxxx", "xxxx");//此处为数据库用户名与密码
} catch (Exception ex) {
ex.printStackTrace();
}
try {
CallableStatement proc=null;
proc=myConnection.prepareCall("{call xs_proc(?,?)}");
proc.setString(1, "zhangsan");
proc.registerOutParameter(2, Types.NUMERIC);
proc.execute();
String teststring=proc.getString(2);
System.out.println(teststring);
} catch (Exception ex) {
ex.printStackTrace();
}
对于列表返回值的存储过程，在上述代码中做简单修改。如下
CallableStatement proc = null ; proc = myConnection.prepareCall( " {call getdcsj(?,?,?,?,?)} " ); proc.setString( 1 , strDate); proc.setString( 2 , jzbh); proc.registerOutParameter( 3 , Types.NUMERIC); proc.registerOutParameter( 4 , OracleTypes.CURSOR); proc.registerOutParameter( 5 , OracleTypes.CURSOR); proc.execute(); ResultSet rs = null ; int total_number = proc.getInt( 3 ); rs = (ResultSet)proc.getObject( 4 );
上述存储过程修改完毕。另外，一个复杂的工程项目中的例子：查询一段数据中间隔不超过十分钟且连续超过100条的数据。即上述代码所调用的getdcsj存储过程
create or replace procedure getDcsj(var_flag in varchar2,
var_jzbh in varchar2,
number_total out number,
var_cursor_a out mypackage.my_cursor,
var_cursor_b out mypackage.my_cursor) is
total number;
cursor cur is
select sj, flag
from d_dcsj
where jzbh = var_jzbh
order by sj desc
for update;
last_time date;
begin
for cur1 in cur loop
if last_time is null or cur1.sj >= last_time - 10 / 60 / 24 then
update d_dcsj set flag = var_flag where current of cur;
last_time := cur1.sj;
else
select count(*) into total from d_dcsj where flag = var_flag;
dbms_output.put_line(total);
if total < 100 then
update d_dcsj set flag = null where flag = var_flag;
last_time := null;
update d_dcsj set flag = var_flag where current of cur;
else
open var_cursor_a for
select *
from d_dcsj
where flag = var_flag
and jzbh = var_jzbh
and zh = 'A'
order by sj desc;
number_total := total;
open var_cursor_b for
select *
from d_dcsj
where flag = var_flag
and jzbh = var_jzbh
and zh = 'B'
order by sj desc;
number_total := total;
exit;
end if;
end if;
end loop;
select count(*) into total from d_dcsj where flag = var_flag;
dbms_output.put_line(total);
if total < 100 then
open var_cursor_a for
select * from d_dcsj where zh = 'C';
open var_cursor_b for
select * from d_dcsj where zh = 'C';
else
open var_cursor_a for
select *
from d_dcsj
where flag = var_flag
and jzbh = var_jzbh
and zh = 'A'
order by sj desc;
number_total := total;
open var_cursor_b for
select *
from d_dcsj
where flag = var_flag
and jzbh = var_jzbh
and zh = 'B'
order by sj desc;
number_total := total;
end if;
commit;
end;
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