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Devart.Data.PostgreSql Namespace / PgSqlCommandBuilder Class
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    PgSqlCommandBuilder Class
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    Automatically generates single-table commands used to reconcile changes made to a System.Data.DataSet with the PostgreSQL.
    Syntax
    'Declaration
     
    Public Class PgSqlCommandBuilder 
       Inherits Devart.Common.DbCommandBuilder
       Implements System.ComponentModel.IComponentSystem.IDisposable 
    Remarks

    The PgSqlDataAdapter does not automatically generate the SQL statements required to reconcile changes made to a System.Data.DataSet associated with PostgreSQL. However, you can create a PgSqlCommandBuilder object that generates SQL statements for single-table updates. After assigning the PgSqlDataAdapter to the PgSqlCommandBuilder, it begins to generate any additional SQL statements that you do not set.

    The relationship between a PgSqlDataAdapter and its corresponding PgSqlCommandBuilder is always one-to-one. To create this correspondence, you set the DataAdapter property of the PgSqlCommandBuilder object. This causes the PgSqlCommandBuilder to register itself as a listener, which produces the output of PgSqlDataAdapter.RowUpdating events that affect the System.Data.DataSet.

    To generate INSERT, UPDATE, or DELETE statements, the PgSqlCommandBuilder uses the PgSqlDataAdapter.SelectCommand property to retrieve a required set of metadata. If you change the value of PgSqlDataAdapter.SelectCommand after the metadata has been retrieved (for example, after the first update), you then should call the Devart.Common.DbCommandBuilderBase.RefreshSchema method to update the metadata.

    The PgSqlCommandBuilder also uses the Connection, CommandTimeout, and System.Data.Common.DbCommand.Transaction properties referenced by the PgSqlDataAdapter.SelectCommand. The user should call Devart.Common.DbCommandBuilderBase.RefreshSchema if any of these properties are modified, or value of the PgSqlDataAdapter.SelectCommand property itself is changed. Otherwise the PgSqlDataAdapter.InsertCommand, PgSqlDataAdapter.UpdateCommand, and PgSqlDataAdapter.DeleteCommand properties retain their previous values.

    If you assign null to corresponding property of PgSqlDataAdapter, the PgSqlCommandBuilder will be disassociated from the PgSqlDataAdapter, and the generated commands will no longer be used.

    Note: This class is not available in .NET Standard 1.3 compatible assembly. It is available only in the assembly for full .NET Framework and .NET Standard 2.0 compatible assembly.

    Example
    The following example uses PgSqlCommand, along with PgSqlDataAdapter and PgSqlConnection, to select rows from PostgreSQL. The example is passed an initialized System.Data.DataSet, a connection string, a query string that is SQL SELECT statement, and a string that is the name of the PostgreSQL table. The example then creates a PgSqlCommandBuilder.
    public DataSet SelectPgSqlSrvRows(DataSet myDataSet,string pgConnection,string mySelectQuery,string myTableName)
    {
      PgSqlConnection myConn = new PgSqlConnection(pgConnection);
      PgSqlDataAdapter myDataAdapter = new PgSqlDataAdapter();
      myDataAdapter.SelectCommand = new PgSqlCommand(mySelectQuery, myConn);
      PgSqlCommandBuilder pgCommandBuilder = new PgSqlCommandBuilder(myDataAdapter);
    
      myConn.Open();
    
      DataSet myDataSet = new DataSet();
      myDataAdapter.Fill(myDataSet, "Departments");
    
      //code to modify data in dataset here
    
      //Without the PgSqlCommandBuilder this line would fail
      myDataAdapter.Update(myDataSet, "Departments");
    
      myConn.Close();
    
      return myDataSet;
    }
    Public Function SelectPgSqlSrvRows(myDataSet As DataSet, pgConnection As String, mySelectQuery As String, myTableName As String) As DataSet
      Dim myConn As New PgSqlConnection(pgConnection)
      Dim myDataAdapter As New PgSqlDataAdapter()
      myDataAdapter.SelectCommand = New PgSqlCommand(mySelectQuery, myConn)
      Dim pgCommandBuilder As PgSqlCommandBuilder = New PgSqlCommandBuilder(myDataAdapter)
    
      myConn.Open()
    
      Dim myDataSet As DataSet = New DataSet
      myDataAdapter.Fill(myDataSet, "Departments")
    
      ' Code to modify data in DataSet here
    
      ' Without the PgSqlCommandBuilder this line would fail.
      myDataAdapter.Update(myDataSet, "Departments")
    
      myConn.Close()
    
      SelectPgSqlSrvRows = myDataSet
    End Function
    Inheritance Hierarchy

    System.Object
       System.MarshalByRefObject
          System.ComponentModel.Component
             System.Data.Common.DbCommandBuilder
                Devart.Common.DbCommandBuilderBase
                   Devart.Common.DbCommandBuilder
                      Devart.Data.PostgreSql.PgSqlCommandBuilder

    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