Oracle函数将行返回到C# [英] Oracle function return rows into c#

问题描述

我想在oracle中创建一个过程或函数，该函数将多行不同类型的返回给我的应用程序.我在互联网上找到了一些示例，但我无法使它正常工作...

I want to create a procedure or function in oracle that returns more than one row of different types to my application. I found some examples on the internet but i can't get it to work...

示例: 我在oracle中创建了一个自定义类型:

Example: I created a custom type in oracle:

create type proc_selectall is object 
    (Mjera varchar2(50),
    Status number(10,0),
    Naziv varchar2(50),
    Stat number(10,0));

然后:

create type ret_selectall is table of proc_selectall;

然后创建函数:

create or replace function fsp_SelectAll return ret_selectall
is
l_ret_selectall ret_selectall := ret_selectall();
n integer := 0;
BEGIN 
    for r in(SELECT JEDINICAMJERE.Mjera,
    JEDINICAMJERE.Status, 
    KATEGORIJE.Naziv, 
    KATEGORIJE.Status as Stat
FROM JEDINICAMJERE, KATEGORIJE)
loop
  l_ret_selectall.extend;
  n := n + 1;
  l_ret_selectall(n) := proc_selectall(r.Mjera, r.Status, r.Naziv, r.Stat);
end loop;
return l_ret_selectall;
END;

当我输入以下行时:

select * from table (fsp_SelectAll)

我得到了不错的预期输出:

I get a nice and expected output:

MJERA | STATUS | NAZIV | STAT
tr      0        name1   1
fd      1        name2   1
ds      1        name3   0
.....

稍后，我尝试在我的应用中获取这些值. 我尝试过这样的事情:

Later i tried to get those values in my app. I tried something like this:

//cmd.Parameters.Add("proc_selectall ", OracleDbType.Object);
//cmd.Parameters.Add("ret_selectall ", OracleDbType.Array);
//cmd.Parameters["ret_selectall "].Direction = ParameterDirection.ReturnValue;
//if (connection.State == ConnectionState.Closed)
//    connection.Open();
//cmd.ExecuteNonQuery();

稍后……

//OracleCommand objCmd = new OracleCommand("select * from table fsp_SelectAll", connection);
//objCmd.CommandType = CommandType.StoredProcedure;
//objCmd.ExecuteNonQuery();
//int size=objCmd.ExecuteReader().FieldCount;

我也尝试过

//adapter = new OracleDataAdapter(cmd);...

但是关于类型，参数总是存在一些错误... (连接到oracle工作.我执行了Insert，Update，Delete程序，它们工作正常)

But there are always some errors about type, parameters... (Connection to oracle work. I executed Insert, Update, Delete procedures and they work fine)

我也尝试创建此过程:(这是我的第一次尝试)

Also i tried to create this procedure: (this was my first try)

CREATE OR REPLACE PROCEDURE osp_SelectAll (Mjera OUT VARCHAR2,
Status OUT NUMBER, Naziv OUT VARCHAR2,Stat OUT NUMBER) AS 
BEGIN 
    SELECT JEDINICAMJERE.Mjera,
    JEDINICAMJERE.Status, 
    KATEGORIJE.Naziv, 
    KATEGORIJE.Status as Stat INTO Mjera, Status, Naziv, Stat
FROM JEDINICAMJERE, KATEGORIJE;
END osp_SelectAll;

但是它不返回任何一行...我放弃了.

But it doesn't return any row or rows... and i give up.

请帮助我，我需要解决这个问题.

Please help me, i need to solve this.

推荐答案

返回用户定义的对象并非易事，这需要大量的额外工作.

Returning a user defined object is not so easy, it requires a lot of additional effort.

尝试一下:

create or replace function fsp_SelectAll return SYS_REFCURSOR is
   res SYS_REFCURSOR;
BEGIN 
    OPEN res FOR
    SELECT JEDINICAMJERE.Mjera,
      JEDINICAMJERE.Status, 
      KATEGORIJE.Naziv, 
      KATEGORIJE.Status as Stat
    FROM JEDINICAMJERE, KATEGORIJE;
    return res;
END;

然后

OracleCommand objCmd = new OracleCommand("fsp_SelectAll", connection);
objCmd.CommandType = CommandType.StoredProcedure;
objCmd.Parameters.Add("res", OracleDbType.RefCursor, ParameterDirection.ReturnValue);

var da = new OracleDataAdapter(objCmd);
var dt = new DataTable();
da.Fill(dt);

或者，如果您愿意，也可以使用ExecuteReader():

Or you can use ExecuteReader(), if you prefer:

OracleDataReader dr = objCmd.ExecuteReader();
while ( dr.Read() ) {
   ...
}
dr.Close();

注意，我从未使用过.CommandType = CommandType.StoredProcedure;.如果失败，请使用以下语法:

Note, I never worked with .CommandType = CommandType.StoredProcedure;. If it fails use this syntax:

OracleCommand objCmd = new OracleCommand("BEGIN :res := fsp_SelectAll; END;", connection);
objCmd.CommandType = CommandType.Text;

这篇关于Oracle函数将行返回到C#的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！