Read schema information using the FillSchema() method of a DataAdapter object

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using System;
using System.Data;
using System.Data.SqlClient;

class FillSchema
{
  public static void Main()
  {
    SqlConnection mySqlConnection =new SqlConnection("server=(local)SQLEXPRESS;database=MyDatabase;Integrated Security=SSPI;");

    SqlCommand mySqlCommand = mySqlConnection.CreateCommand();
    mySqlCommand.CommandText =
      "SELECT ProductID, ProductName " +
      "FROM Products;" +
      "SELECT OrderID " +
      "FROM Orders;" +
      "SELECT OrderID, ProductID, UnitPrice " +
      "FROM [Order Details];";
    SqlDataAdapter mySqlDataAdapter = new SqlDataAdapter();
    mySqlDataAdapter.SelectCommand = mySqlCommand;
    DataSet myDataSet = new DataSet();
    mySqlConnection.Open();
    mySqlDataAdapter.FillSchema(myDataSet, SchemaType.Mapped);
    mySqlConnection.Close();
    myDataSet.Tables["Table"].TableName = "Products";
    myDataSet.Tables["Table1"].TableName = "Orders";
    myDataSet.Tables["Table2"].TableName = "Order Details";

    foreach (DataTable myDataTable in myDataSet.Tables)
    {
      Console.WriteLine("

Reading from the " +
        myDataTable + "DataTable:
");

      foreach (DataColumn myPrimaryKey in myDataTable.PrimaryKey)
      {
        Console.WriteLine("myPrimaryKey = " + myPrimaryKey);
      }

      foreach (Constraint myConstraint in myDataTable.Constraints)
      {
        Console.WriteLine("myConstraint.IsPrimaryKey = " + ((UniqueConstraint) myConstraint).IsPrimaryKey);
        foreach (DataColumn myDataColumn in ((UniqueConstraint) myConstraint).Columns)
        {
          Console.WriteLine("myDataColumn.ColumnName = " + myDataColumn.ColumnName);
        }
      }

      foreach (DataColumn myDataColumn in myDataTable.Columns)
      {
        Console.WriteLine("
myDataColumn.ColumnName = " + myDataColumn.ColumnName);
        Console.WriteLine("myDataColumn.DataType = " + myDataColumn.DataType);

        Console.WriteLine("myDataColumn.AllowDBNull = " + myDataColumn.AllowDBNull);
        Console.WriteLine("myDataColumn.AutoIncrement = " + myDataColumn.AutoIncrement);
        Console.WriteLine("myDataColumn.AutoIncrementSeed = " + myDataColumn.AutoIncrementSeed);
        Console.WriteLine("myDataColumn.AutoIncrementStep = " + myDataColumn.AutoIncrementStep);
        Console.WriteLine("myDataColumn.MaxLength = " + myDataColumn.MaxLength);
        Console.WriteLine("myDataColumn.ReadOnly = " + myDataColumn.ReadOnly);
        Console.WriteLine("myDataColumn.Unique = " + myDataColumn.Unique);
      }
    }
  }
}