[dba-VB] Update gets string or binary truncation error

Hi John

That is what the DataTableAdapter is for. If you use the wizard for creating these to attach your tables, it will do all the plumbing and create a (giant) class which wraps all this for you taking care of relations, not null, max lengths, strong types, error handling etc. etc. not to say provide the basis for creating all the queries you need including ready-made basic queries for CRUD as well as giving you the choice to use stored procedures, pass-through or normal queries. 

All of this is controlled from a graphic layout like a relations view. If that isn't enough it also lets you carry on with Data Access Layers and business rules.

Nothing is hidden or secret. You can browse the class should you have the patience and wish so. This is a snippet:

            private void InitClass() {
                this.columnKundeNr = new global::System.Data.DataColumn("KundeNr", typeof(int), null, global::System.Data.MappingType.Element);
                base.Columns.Add(this.columnKundeNr);
                this.columnNavn = new global::System.Data.DataColumn("Navn", typeof(string), null, global::System.Data.MappingType.Element);
                base.Columns.Add(this.columnNavn);
                this.columnAdr1 = new global::System.Data.DataColumn("Adr1", typeof(string), null, global::System.Data.MappingType.Element);
                base.Columns.Add(this.columnAdr1);
                this.columnAdr2 = new global::System.Data.DataColumn("Adr2", typeof(string), null, global::System.Data.MappingType.Element);
                base.Columns.Add(this.columnAdr2);
                this.columnPostNr = new global::System.Data.DataColumn("PostNr", typeof(string), null, global::System.Data.MappingType.Element);
                base.Columns.Add(this.columnPostNr);
                this.columnBynavn = new global::System.Data.DataColumn("Bynavn", typeof(string), null, global::System.Data.MappingType.Element);
                base.Columns.Add(this.columnBynavn);
                this.columnTlf = new global::System.Data.DataColumn("Tlf", typeof(string), null, global::System.Data.MappingType.Element);
                base.Columns.Add(this.columnTlf);
                this.Constraints.Add(new global::System.Data.UniqueConstraint("Constraint1", new global::System.Data.DataColumn[] {
                                this.columnKundeNr}, true));
                this.columnKundeNr.AllowDBNull = false;
                this.columnKundeNr.Unique = true;
                this.columnNavn.AllowDBNull = false;
                this.columnNavn.MaxLength = 50;
                this.columnAdr1.MaxLength = 50;
                this.columnAdr2.MaxLength = 50;
                this.columnPostNr.MaxLength = 50;
                this.columnBynavn.MaxLength = 50;
                this.columnTlf.MaxLength = 50;
            }

If you redesign the table structure from within Visual Studio, it will track the changes and adjust the class accordingly. 
  
It is  __so clever__  that I wonder why most are still moving on with SQL builders, hand built command strings and the like - pure waste of time in my opinion - except for programmers with special needs and knowledge like Shamil who knows what he is doing.

William, I think, will amen this. 

I must admit that because of VS2008 I'm ready to forgive MS much of their bad doings.

/gustav

>>> jwcolby at colbyconsulting.com 29-04-2008 15:53 >>>
I am doing the update thing, updating data back to SQL Server.  I have 
been updating an ADO recordset in memory and when I try to update it 
back to SQL Server it throws an error that the update failed because it 
would cause a string value to be truncated.

How is this possible.  I thought that the table structure in memory 
mirrored the structure in the data store (SQL Server in this instance). 
  Doesn't the read of the data out of SQL Service discover the field 
size and type and build a similar structure in memory?

Apparently not, but if not how do I handle a case like this?
-- 
John W. Colby
www.ColbyConsulting.com