dmcafee at pacbell.net
dmcafee at pacbell.net
Wed Feb 23 11:29:37 CST 2005
This is what I just read yesterday: Moving from ADO to ADO.NET If you've used ADO, you'll want to understand how the syntax of ADO.NET differs. But before exploring the changes, be aware that you CAN you ADO in a VB.NET program if you want. Instead of making ADO.NET itself backward compatible with ADO, MS has chosen to make ASP.NET embrace ADO for those who can't or won't make the move over to ADO.NET. Rest assured that the entire ADO object model is still available. Now, though, you also have available an additional set of classes particular to the .NET framework, collectively referred to as ADO.NET When you connect to a database using ASP.NET, you can use the native SQL provider or the ADO.NET provider. If you are accessing a data source such as Access, Excel, CSV or some other straightforward variety, you must use the ADO.NET provider. If your db is MS SQL Server, you can use the somewhat faster SQL provider. The ADO.NET provider also works with SQL but is a bit slower. So, as Charlotte mentioned, maybe using datasets for Access and do it the old fashioned way for SQL. I'm also having a fun time in my transition to .Net :( D -----Original Message----- From: accessd-bounces at databaseadvisors.com [mailto:accessd-bounces at databaseadvisors.com]On Behalf Of Charlotte Foust Sent: Wednesday, February 23, 2005 8:30 AM To: Access Developers discussion and problem solving Subject: RE: [AccessD] Making SQL Server NewID() work with a dataset in .net Yes, it is. The problem only occurs with a SQL Server backend. An Access backend doesn't experience the problem. One of the nice things about .Net is that you can create separate data providers to handle SQL Server and Access, so the details are not dealt with by the UI programmer, only by the data tier programmer. Of course, if you happen to be both ... <g> Charlotte Foust -----Original Message----- From: Gustav Brock [mailto:Gustav at cactus.dk] Sent: Wednesday, February 23, 2005 1:09 AM To: accessd at databaseadvisors.com Subject: [AccessD] Making SQL Server NewID() work with a dataset in .net Hi all using dotnet. Snipped this from the ElementK Tips. I have not used the datagrid from dotnet and have to ask if this really is the way to handle this task? From an Access view it seems like moving to the stone age. Or would I just use another more clever grid? /gustav Making SQL Server primary key NEWID() default values work with a Visual Basic .NET DataSet (Visual Basic .NET/SQL 2000) Designing a SQL Server table to use the uniqueidentifier datatype for its primary key column and then giving it a default with the NEWID() function is a great way to manage your data; however, there can be a slight snag if you use ADO.NET's DataSet in Visual Basic .NET with such a table. In this scenario, adding records in a DataGrid in Visual Basic .NET will cause an error. The primary key field doesn't allow NULL values. We know that the key field will be defaulted on the SQL Server side, but Visual Basic .NET enforces the NULL before the data is pushed to SQL Server. The solution is easy, since we have access to the dataset XML. First, we can delete the key from the dataset table by right-clicking on the table and selecting the Delete Key. The field isn't deleted, just the key indicator for the field. Now the field won't require a unique value, but we still need to allow the value to be NULL. This is done by adding minOccurs="0" to the <xs:element> code for this field, as in the example below: <xs:element name="KeyFieldName" msdata:DataType="System.Guid, mscorlib, version=1.0.3300.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" type="xs:string" minOccurs="0" /> Now records can be added to the grid without raising any errors, and SQL Server will use the NEWID() default for primary key column values once the table is updated. -- AccessD mailing list AccessD at databaseadvisors.com http://databaseadvisors.com/mailman/listinfo/accessd Website: http://www.databaseadvisors.com -- AccessD mailing list AccessD at databaseadvisors.com http://databaseadvisors.com/mailman/listinfo/accessd Website: http://www.databaseadvisors.com