Oracle存储过程全解及java调用示例
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
create or replace procedure xs_proc_no is
begin
insert into xuesheng values ( 3 , ' wangwu ' , 90 , 90 );
commit ;
end xs_proc_no;
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;
二、程序调用
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();
}
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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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