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
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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