c# - 如何将数据表转换为相关数据集

Question

我在 DataTable 中对数据进行了非规范化。

数据包含员工姓名，以及他们在一系列薪酬周期中获得的薪酬。IE：

我的数据表包含：

Employee 1    Jan-1-2012     $100
Employee 2    Jan-1-2012     $300
Employee 1    Feb-1-2012     $400
Employee 2    Feb-1-2012     $200
Employee 1    Mar-1-2012     $150
Employee 2    Mar-1-2012     $325

如何将此数据加载到父 DataTable 包含员工姓名而子 DataTable 包含薪水详细信息的 DataSet 中？

Answer 1

DataSet 只不过是 DataTables 的集合。所以要将数据表“加载”到 dataSet 中简单添加它：

        DataTable employees = new DataTable();
        DataTable payCheckes = new DataTable();
        DataSet ds = new DataSet();
        ds.Tables.Add(employees);
        ds.Tables.Add(payCheckes);

你想以某种方式“组合”数据表吗？获取每个员工的薪水？

Answer 2

无需手动插入的代码：

       DataSet ds = new DataSet();
        DataTable dtemploye = new DataTable();
        DataTable dtpayment = new DataTable();

        ds.Tables.AddRange(new DataTable[] { dtemploye, dtpayment });
        DataColumn dcIdemploye = dtemploye.Columns["ID_EMPLOYEE"];
        DataColumn dcIdemployeprice = dtpayment.Columns["ID_EMPLOYEE"];
        DataRelation drrelation = new DataRelation("relemploy_payment", dcIdemploye, dcIdemployeprice);
        ds.Relations.Add(drrelation);

Answer 3

      DataSet ds = new DataSet();
        DataTable dtemploye = new DataTable();
        DataColumn dcnameemploye = new DataColumn();
        DataColumn dcIdemploye = new DataColumn();
        dtemploye.Columns.AddRange(new DataColumn[]{dcnameemploye,dcIdemploye});

        DataTable dtpayment = new DataTable();
        DataColumn dtprice = new DataColumn();
        DataColumn dtDate = new DataColumn();
        DataColumn dcIdemployeprice = new DataColumn();
        dtpayment.Columns.AddRange(new DataColumn[]{dcIdemployeprice,dtprice,dtDate});

        DataRow drrowemploy = dtemploye.NewRow();
        drrowemploy[0] = "1";
        drrowemploy[1] = "Employee 1";
        dtemploye.Rows.Add(drrowemploy);

        DataRow drrowpayment = dtpayment.NewRow();
        drrowpayment[0] = "1";
        drrowpayment[0] = "01/01/2012";
        drrowpayment[1] = " 300";


        ds.Tables.AddRange(new DataTable[]{dtemploye, dtpayment});

        DataRelation drrelation = new DataRelation("relemploy_payment", dcIdemploye, dcIdemployeprice);
        ds.Relations.Add(drrelation);