如何在Java中访问从PostgreSQL返回setof refcursor的过程？ [英] How to access the procedure that return setof refcursor from PostgreSQL in Java?

问题描述

需要访问从PostgreSQL返回setof refcursor的过程。

Need to access a procedure that return setof refcursor from PostgreSQL.

我能够访问第一个对象，但不能访问其余对象而不是其余对象。

I am able to access the first object but not rest of object not rest of objects.

    con.setAutoCommit(false);
    try (CallableStatement proc = 
             con.prepareCall("{ ? = call usp_sel_article_initialdata_new1() }")) {
        proc.registerOutParameter(1, Types.OTHER);
        proc.execute();
        ResultSet results = (ResultSet) proc.getObject(1); 
        while (results.next()) {
            System.out.println("Result Id" + results.getString(1));
            System.out.println("Results Name" + results.getString(2));
    }

这给了我第一个refcursor值，但当我尝试使用第二个refcursor时给我错误
我用这一行：

This give me the first refcursor values but when i try to use second refcursor it give me error I use this line:

proc.registerOutParameter(2, Types.OTHER);

这是错误的。还试过：

proc.registerOutParameter(1, Types.REF);

这也行不通。
过程示例是：

This also not work. Procedure Example is:

    CREATE OR REPLACE FUNCTION usp_sel_article_initialdata_new1()
    RETURNS SETOF refcursor AS
    $BODY$
    Declare swv_refcur refcursor;
    swv_refcur2 refcursor;
    DECLARE r record;
    BEGIN

    open SWV_RefCur for Select OM.opID as ID,OM.OperatorName as Name from operator
    AS OM (OPid bigint,OperatorName character varying(100),status boolean)
    where OM.status = true 
    order By OperatorName;
    return next SWV_RefCur;

    open SWV_RefCur2 for Select CC.cirid as ID,CC.cirnm as Name from  circle 
    AS CC (cirid bigint,cirnm character varying(100),status boolean)
    where Status = true and cirid not in(28,31) 
    order by cirnm;
    return next SWV_RefCur2;

请帮我看看如何访问第二个对象。

Please help me how to access second object.

推荐答案

返回setof refcursor 表示您获得常规 ResultSet 调用 getObject（）时，row包含另一个 ResultSet：

returns setof refcursor means you get a regular ResultSet where each "row" contains another ResultSet when calling getObject():

以下作品对我来说：

ResultSet rs = stmt.executeQuery("select * from usp_sel_article_initialdata_new1()");
if (rs.next())
{
  // first result set returned
  Object o = rs.getObject(1);
  if (o instanceof ResultSet)
  {
    ResultSet rs1 = (ResultSet)o;
    while (rs1.next())
    {
       int id = rs1.getInt(1);
       String name = rs1.getString(2);
       .... retrieve the other columns using the approriate getXXX() calls
    }
  }
}

if (rs.next()) 
{
  // process second ResultSet 
  Object o = rs.getObject(1);
  if (o instanceof ResultSet)
  {
    ResultSet rs2 = (ResultSet)o;
    while (rs2.next())
    {
       ......
    }
  }
}

从 psql 中你也可以使用 select * from usp_sel_article_initialdata_new1（）之后您只需要使用 FETCH ALL 。有关示例，请参阅手册： http：//www.postgresql。 org / docs / current / static / plpgsql-cursors.html＃AEN59018

From within psql you can also use select * from usp_sel_article_initialdata_new1() you just need to use FETCH ALL afterwards. See the manual for an example: http://www.postgresql.org/docs/current/static/plpgsql-cursors.html#AEN59018

postgres=> select * from usp_sel_article_initialdata_new1();
 usp_sel_article_initialdata_new1
----------------------------------
 <unnamed portal 1>
 <unnamed portal 2>
(2 rows)

postgres=> fetch all from "<unnamed portal 1>";
 ?column?
----------
        1
(1 row)

postgres=> fetch all from "<unnamed portal 2>";
 ?column?
----------
        2
(1 row)

postgres=>

（我为上面的例子创建了一个虚函数，只返回值<$的单行c $ c> 1 表示第一个游标， 2 表示第二个游标）

(I created a dummy function for the above example that only returns a single row with the value 1 for the first cursor and 2 for the second cursor)

编辑：

为了实现这一点，需要在事务中运行。因此必须关闭自动提交：

In order for this to work, this needs to be run inside a transaction. Therefor autocommit must be turned off:

connection.setAutoCommit(false);

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