使用Dapper读取Oracle多个结果集

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发布于 2022-05-10 13:59:15

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发布于 2022-05-10 13:59:15

Dapper对SQL Server支持很好，但对于Oracle有些用法不一样，需要自己进行特殊处理。

1、首先要自定义一个Oracle参数类

  public class OracleDynamicParameters : SqlMapper.IDynamicParameters
     {
         private readonly DynamicParameters dynamicParameters = new DynamicParameters();
 
         private readonly List<OracleParameter> oracleParameters = new List<OracleParameter>();
 
         public void Add(string name, OracleDbType oracleDbType, ParameterDirection direction, object value = null, int? size = null)
         {
             OracleParameter oracleParameter;
             if (size.HasValue)
             {
                 oracleParameter = new OracleParameter(name, oracleDbType, size.Value, value, direction);
             }
             else
             {
                 oracleParameter = new OracleParameter(name, oracleDbType, value, direction);
             }
 
             oracleParameters.Add(oracleParameter);
         }
 
         public void Add(string name, OracleDbType oracleDbType, ParameterDirection direction)
         {
             var oracleParameter = new OracleParameter(name, oracleDbType, direction);
             oracleParameters.Add(oracleParameter);
         }
 
         public void AddParameters(IDbCommand command, SqlMapper.Identity identity)
         {
             ((SqlMapper.IDynamicParameters)dynamicParameters).AddParameters(command, identity);
 
             var oracleCommand = command as OracleCommand;
 
             if (oracleCommand != null)
             {
                 oracleCommand.Parameters.AddRange(oracleParameters.ToArray());
             }
         }
     }

2、对于一个sql语句中的多个结果集处理

 string sql = @"
begin
open :rslt1 for select * from t_um_event where rownum<10
and c_fid>:fid;

open :rslt2 for select count(*) as count from t_um_event;
end;
                    ";
                OracleDynamicParameters dynParams = new OracleDynamicParameters();


                dynParams.Add(":rslt1", OracleDbType.RefCursor, ParameterDirection.Output);
                dynParams.Add(":rslt2", OracleDbType.RefCursor, ParameterDirection.Output);
                dynParams.Add(":fid", OracleDbType.Int64, ParameterDirection.Input, 1000);
                using (var muti = cn.QueryMultiple(sql, param: dynParams))
                {
                    List<TestClass> firstRes = muti.Read<TestClass>().ToList();
                    RecordCount secondRes = muti.ReadFirstOrDefault<RecordCount>();
                }

    class TestClass
    {
        public string C_ID
        {
            get;
            set;
        }
        public DateTime? C_REG_TIME
        {
            get;
            set;
        }
        public string C_Title
        {
            get;
            set;
        }
    }

    class RecordCount
    {
        public int Count { get; set; }
    }

2、对于oracle存储过程的多个结果集处理，存储过程定义

create or replace package pkg_test_dapper is

  TYPE t_cursor IS REF CURSOR;

  procedure p_get_list(cur_out1 out t_cursor,
                       p_fid    int,
                       cur_out2 out t_cursor);
  procedure p_get_count(cur_out out t_cursor);
end pkg_test_dapper;
/
create or replace package body pkg_test_dapper is

  procedure p_get_list(cur_out1 out t_cursor,
                       p_fid    int,
                       cur_out2 out t_cursor) as
  begin
    open cur_out1 for
      select *
        from t_um_event
       where rownum < 10
         and c_fid > p_fid;
    open cur_out2 for
      select count(*) as count from t_um_event;
  end;
  procedure p_get_count(cur_out out t_cursor) as
  begin
    open cur_out for
      select count(*) as count from t_um_event;
  end;
end pkg_test_dapper;
/

c#中用dapper调用存储过程返回oracle多个结果集

   using (IDbConnection cn = new OracleConnection(ConfigurationManager.ConnectionStrings["ZWGCDB"].ConnectionString))
            {

                TestClass Evt = cn.QueryFirstOrDefault<TestClass>("select * from t_um_event where c_id=:Id", new { id = "1BA2BF30-658A-4A79-A179-05A77C527150" });

                //int cnt = cn.Execute("update t_um_event set c_reg_time=:reg_time where c_id=:id", new { id = "CEA00DA2-79D2-48CC-A9E1-D3CBB3842E54", reg_time = DateTime.Now });

              

                OracleDynamicParameters dynParams = new OracleDynamicParameters();

                dynParams.Add("cur_out1", OracleDbType.RefCursor, ParameterDirection.Output);
                dynParams.Add("cur_out2", OracleDbType.RefCursor, ParameterDirection.Output);
                dynParams.Add("p_fid", OracleDbType.Int64, ParameterDirection.Input, 1000);

                using (var muti = cn.QueryMultiple("pkg_test_dapper.p_get_list", dynParams, commandType: CommandType.StoredProcedure))
                {
                    List<TestClass> firstRes = muti.Read<TestClass>().ToList();
                    RecordCount secondRes = muti.ReadFirstOrDefault<RecordCount>();
                }
            }

参考：http://stackoverflow.com/questions/18772781/using-dapper-querymultiple-in-oracle

使用到的包文件如下：

<?xml version="1.0" encoding="utf-8"?>
<packages>
  <package id="Dapper" version="1.50.2" targetFramework="net40" />
  <package id="Oracle.ManagedDataAccess" version="12.1.24160419" targetFramework="net40" />
</packages>

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原始发表：2022-03-28，如有侵权请联系 cloudcommunity@tencent.com 删除

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