Hive(四):c#通過odbc訪問hive

      hive odbc 驅動配置成功后，通過c#訪問就變得比較簡單了，分為查詢與更新操作，直接附上測試代碼。在此過程中需要注意c#工程編譯的目標平台

• 讀寫訪問代碼示例：

  public class HiveOdbcClient
      {
          /// <summary>
          /// 
          /// </summary>
          public static HiveOdbcClient Current
          {
              get { return new HiveOdbcClient(); }
          }
  
          /// <summary>
          /// 
          /// </summary>
          /// <param name="context"></param>
          public void ExcuteNoQuery(string dns, string sql)
          {
              OdbcConnection conn = null;
  
              try
              {
                  conn = new OdbcConnection(dns);
                  conn.Open();
                  OdbcCommand cmd = new OdbcCommand(sql, conn);
                  cmd.ExecuteNonQuery();
              }
              catch (Exception ex)
              {
                  throw ex;
              }
              finally
              {
                  if (null != conn)
                  {
                      conn.Close();
                  }
              }
          }
  
          /// <summary>
          /// 
          /// </summary>
          /// <param name="context"></param>
          /// <returns></returns>
          public DataSet Query(string dns, string sql,string tblName = "tbl")
          {
              DataSet set = new DataSet();
              OdbcConnection conn = null;
  
              try
              {
                  conn = new OdbcConnection(dns);
                  conn.Open();
                  OdbcCommand cmd = conn.CreateCommand();
                  cmd.CommandText = sql;
                  OdbcDataAdapter adapter = new OdbcDataAdapter(cmd);
                  adapter.Fill(set, tblName);
              }
              catch (Exception ex)
              {
                  throw ex;
              }
              finally
              {
                  if (null != conn)
                  {
                      conn.Close();
                  }
              }
  
              return set;
          }
      }

• 測試：新建一個控制台工程，測試表創建及數據插入，示例代碼如下：

  class Program
      {
  
          static void Main(string[] args)
          {
              Console.WriteLine("按任意鍵開始進行建表及數據插入測試");
              Console.ReadKey();
  
              string dns = "DSN=myhive;UID=hive;PWD=";
  
              string sql = "create table Employee(ID string,Code string,Name string)";
              HiveOdbcClient.Current.ExcuteNoQuery(dns,sql);
  
              sql = "insert into table Employee values('002','002','zhangShan');";
              HiveOdbcClient.Current.ExcuteNoQuery(dns, sql);
  
              Console.WriteLine("數據插入完成，按任意鍵退出");
              Console.ReadKey();
          }
          
      }

• 使用上一章介紹的SQurriel 工具，執行: Select * from employee  ,顯示代碼中插入的數據則OK