Question

鉴于这个oracle存储过程包：

CREATE OR REPLACE 
PACKAGE TESTPKG AS 
  FUNCTION TestReturnRefCursor RETURN SYS_REFCURSOR;
  PROCEDURE TestingRefCursorsAsOutParam (outp OUT SYS_REFCURSOR);
END TESTPKG

这个包体：

CREATE OR REPLACE
PACKAGE BODY TESTPKG AS

  FUNCTION TestReturnRefCursor RETURN SYS_REFCURSOR AS
    outp SYS_REFCURSOR;
  BEGIN
    OPEN outp FOR SELECT * FROM TABLENAME;
    RETURN outp; 
  END TestReturnRefCursor;

  PROCEDURE TestingRefCursorsAsOutParam (outp OUT SYS_REFCURSOR) AS 
  BEGIN
    OPEN outp FOR SELECT * FROM TABLENAME;
  END TestingRefCursorsAsOutParam;

END TESTPKG;

我正在尝试使用Dapper来调用任一函数。我创建了OracleDynamicParameters类，它实现了我在搜索StackOverflow后在这篇文章中找到的Dapper.SqlMapper.IDynamicParameters：https://gist.github.com/vijaysg/3096151

使用以下代码调用TestReturnRefCursor存储函数可以正常工作：

        var conn = new OracleConnection(ConfigurationManager.ConnectionStrings["DataConnection"].ConnectionString);
        conn.Open();
        var p = new OracleDynamicParameters();
        p.Add("retSet", dbType: OracleDbType.RefCursor, direction: ParameterDirection.ReturnValue);
        conn.Execute("TESTPKG.TestReturnRefCursor ", param: p, commandType: CommandType.StoredProcedure);
        var refcur = p.Get<OracleRefCursor>("retSet");
        // do something with refcur
        conn.Close();

但是，当我尝试使用以下代码调用TestingRefCursorsAsOutParam存储过程时：

var conn = new OracleConnection(ConfigurationManager.ConnectionStrings["DataConnection"].ConnectionString);
conn.Open();
var p = new OracleDynamicParameters();
p.Add("retSet", dbType: OracleDbType.RefCursor, direction: ParameterDirection.Output);
conn.Execute("TESTPKG.TestingRefCursorsAsOutParam ", param: p, commandType: CommandType.StoredProcedure);
var refcur = p.Get<OracleRefCursor>("retSet");
// do something with refcur
conn.Close();

我从Oracle.ManagedDataAccess.dll获得了一个带有详细信息的OracleException：

"ORA-06550: line 1, column 7:\nPLS-00306: wrong number or types of arguments in call to 'TESTINGREFCURSORSASOUTPARAM'\nORA-06550: line 1, column 7:\nPL/SQL: Statement ignored"

我在搜索了另一个stackoverflow帖子后发现有时参数没有绑定，如果它们是null，除非你专门将它们的值设置为DBNull.Value，所以我尝试将add参数行更改为：

p.Add("retSet", value: DBNull.Value, dbType: OracleDbType.RefCursor, direction: ParameterDirection.Output);

但这没有帮助。

我可以使用常规的c＃oracle代码调用这个存储过程：

var cmd = conn.CreateCommand();
cmd.CommandText = "TESTPKG.TestingRefCursorsAsOutParam";
cmd.CommandType = CommandType.StoredProcedure;

var outparam = new OracleParameter();
outparam.ParameterName = "retSet";
outparam.Direction = ParameterDirection.Output;
outparam.OracleDbType = OracleDbType.RefCursor;

cmd.Parameters.Add(outparam);

OracleDataAdapter da = new OracleDataAdapter(cmd);
cmd.ExecuteNonQuery();

var refcur = (OracleRefCursor)cmd.Parameters[0].Value;

我在这里缺少什么，或者Dapper无法正常运作？

Answer 1

如果您不想使用精简版（即Query<YourStrongType>）为结果使用强类型，则可以使用Query<dynamic>，以下代码应该有效：

 IEnumerable<dynamic> results = null;
 using (var conn = new OracleConnection(ConfigurationManager.ConnectionStrings["DataConnection"].ConnectionString))
{
    var p = new OracleDynamicParameters();
    p.Add("outp ", dbType: OracleDbType.RefCursor, direction: ParameterDirection.Output);
    results = conn.Query<dynamic>("TESTPKG.TestingRefCursorsAsOutParam", p, commandType: CommandType.StoredProcedure);

    foreach (var row in results)
    {
         var fields = row as IDictionary<string, object>;
    }
}

使用带有C＃的Dapper调用带有refcursor作为out参数的Oracle存储过程的问题，但是refcursor作为返回值有效

1 个答案: