Question

试图通过邮资库的储存功能进行取样,并使用JDBC提供的可呼吁声明。

在此,我的一些试验守则

Consumer bean =new Consumer();
CallableStatement pstmt = null;
try {
con.setAutoCommit(false);
String  query = "{ ? = call getData( ? ) }";
pstmt = con.prepareCall(query); 
 pstmt.registerOutParameter(1, Types.OTHER);
      pstmt.setInt(2,5);
      pstmt.execute(); // execute update statement
      bean=(Consumer)pstmt.getObject(1);
       System.out.println("bean"+bean.getConsumer_name());

我的储存功能是形式。

CREATE FUNCTION getData(int) RETURNS SETOF db_consumer AS $$
 SELECT * FROM db_consumer WHERE consumer_id = $1;
$$ LANGUAGE SQL;

然而,在我试图操作该法典时,我会发现以下错误。

org.postgresql.util.PSQLException: A CallableStatement was executed with an invalid    number of  parameters .

为什么会发生这种情况?

Answer 1

我不认为你需要一个可呼吁的声明,因为你应当能够直接操作<条码>。

PreparedStatement pstmt = con.prepareStatement("select * from getData(?)")
pstmt.setInt(1,5);
ResultSet rs = pstmt.execute(); 
while (rs.next()) {
  System.out.println(rs.getString(1));
}

Answer 2

You are trying to call a SETOFF function via a Callable Statement. That s not going to happen! You ll always get an error.

PostgreSQL s stored functions can return results in two different ways. The function may return either a refcursor value or a SETOF some datatype. Depending on which of these return methods are used determines how the function should be called.
Functions that return data as a set should not be called via the CallableStatement interface, but instead should use the normal Statement or PreparedStatement interfaces.

友情链接