Tài liệu Adding Records with a GUID Primary Key pdf

... [ Team LiB ] Recipe 4.6 Adding Records with a GUID Primary Key Problem You want to add records to a DataTable that uses a GUID as its primary key and has related child records. Solution ... having a GUID primary key column with the DefaultValue set to a new GUID. A relation based on the parent table GUID and a foreign key GUID in the c...

Ngày tải lên: 21/01/2014, 11:20

... parent table. Updating the Primary Key of a Parent Table and Pushing the Change to the Database In this section you'll learn what happens if you attempt to update the primary key in a ... DataTable. This is the default. None Indicates that no action takes place. SetDefault Indicates that the DataColumn values in the child DataTable are to be set to the value in the Defa...

Ngày tải lên: 24/12/2013, 01:17

... mySqlDataAdapter to mySqlTransaction: SqlTransaction mySqlTransaction = mySqlConnection.BeginTransaction(); mySqlDataAdapter.SelectCommand.Transaction = mySqlTransaction; mySqlDataAdapter.InsertCommand.Transaction ... in a DataAdapter. Using the DataAdapter Command Object's Transaction Property A DataAdapter stores four Command objects that you access using the SelectCommand,...

Ngày tải lên: 24/12/2013, 01:17

... number of records in the result set for the DataReader without iterating through all of the records. Additionally, because the DataReader is forward-only, you cannot move backwards in DataReader ... forward-only, read-only access to a stream of rows from a data source. It is optimized for performance by reading data directly from a connection to a data source. As a result, th...

Ngày tải lên: 24/12/2013, 05:15

... statement to create a table in the database and a primary key on the new table in a SQL Server database. You can programmatically drop a table using the DROP TABLE statement in a similar way. ... Command object—to add a table to an existing SQL Server database. The C# code is shown in Example 10-8 . Example 10-8. File: AddTableToDatabaseForm.cs // Namespaces, variables,...

Ngày tải lên: 21/01/2014, 11:20

... dtResults As New DataTable() Try odaResults.Fill(dtResults) Catch excp As Exception MessageBox.Show(excp.Message) Exit Sub End Try ' Assign the data table to the data grid's ... strSQL ' Use the SQL String to build the data adapter and fill the data table. Dim odaResults As New OleDb.OleDbDataAdapter(Me.lblSQLString.Text, _ BuildCnnStr("(local)&qu...

Ngày tải lên: 21/01/2014, 12:20

... modaCust As OleDb.OleDbDataAdapter 6. Private mdtCust As DataTable = New DataTable() These lines of code declare a data adapter and a data table that will be used throughout the form. Note Adding ... Label Name Label1 Caption Customer ComboBox Name cboCustomers Label Name Label2 Caption Customer ID Label Name Label3 Caption Company Name Label Name Label4 Caption Address...

Ngày tải lên: 21/01/2014, 12:20

... equations and a diffusion approximation. Several test cases are treated and a problem appearing in glass manufacturing processes is computed. The results clearly show the advantages of a domain ... flow, decaying shear flow and the driven cavity flow are presented. The numerical solutions are obtained for stationary as well as instationary cases and are com- pared with the analytical...

Ngày tải lên: 15/02/2014, 13:20

... complete: • A plug and play operating system • A plug and play BIOS • Plug and play hardware Legacy Cards are hardware designed prior to Plug and Play which, when installed, will not automatically ... allows faster access; RAM, ROM, or virtual memory? A: RAM 41. What batch file command will stop a batch file operation until a key is pressed? A: PAUSE 42. What is the IS int...

Ngày tải lên: 11/12/2013, 14:15