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Devart.Data.PostgreSql Namespace / PgSqlCommand Class
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    PgSqlCommand Class
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    Represents a SQL statement or stored procedure to execute against PostgreSQL.
    Syntax
    Remarks
    The PgSqlCommand class provides the following methods for executing commands against the PostgreSQL database:
    Item Description
    ExecuteReader Executes commands that return rows.
    ExecutePageReader Returns a specific subset of rows when paging through the results of a query.
    ExecuteNonQuery Executes SQL commands such as INSERT, DELETE, UPDATE.
    ExecuteScalar Retrieves a single value (for example, an aggregate value) from a data source.

    If execution of the command results in a fatal PgSqlException, the PgSqlConnection may close. However, the user can reopen the connection and continue.

    This class supports cross-form data binding with the InterForm Technology.

    Example
    The following example uses the ExecuteReader method of PgSqlCommand, along with PgSqlDataReader and PgSqlConnection, to select rows from a table.
    public void ReadMyData(string myConnString)
    {
      string mySelectQuery = "SELECT DeptNo, DName FROM Test.Dept";
      PgSqlConnection pgConnection = new PgSqlConnection(myConnString);
      PgSqlCommand pgCommand = new PgSqlCommand(mySelectQuery,pgConnection);
      pgConnection.Open();
      PgSqlDataReader pgReader = pgCommand.ExecuteReader();
      try
      {
        while (pgReader.Read())
        {
          Console.WriteLine(pgReader.GetInt32(0).ToString() + ", " + pgReader.GetString(1));
        }
      }
      finally
      {
      // always call Close when done reading.
      pgReader.Close();
      // always call Close when done reading.
      pgConnection.Close();
      }
    }
    Public Sub ReadMyData(myConnString As String)
      Dim mySelectQuery As String = "SELECT DeptNo, DName FROM Test.Dept"
      Dim pgConnection As New PgSqlConnection(myConnString)
      Dim pgCommand As New PgSqlCommand(mySelectQuery, pgConnection)
      pgConnection.Open()
      Dim pgReader As PgSqlDataReader = pgCommand.ExecuteReader()
      Try
        While pgReader.Read()
          Console.WriteLine(pgReader.GetInt32(0).ToString() + ", " _
            + pgReader.GetString(1))
        End While
      Finally
          ' always call Close when done reading.
          pgReader.Close()
          ' always call Close when done with connection.
          pgConnection.Close()
      End Try
    End Sub
    Inheritance Hierarchy

    System.Object
       System.MarshalByRefObject
          System.ComponentModel.Component
             System.Data.Common.DbCommand
                Devart.Common.DbCommandBase
                   Devart.Data.PostgreSql.PgSqlCommand

    Requirements

    Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

    See Also