Sql_server - is this really a bug?

Databases
1

I have just opened up the SQL Server Example - Run it - All good

I have then just changed the Table Name so I can try accessing my own data but am getting a crash
On looking at the message it says
“Error retrieving large column values due to a bug in the SQL Native Client (https://connect.microsoft.com/SQLServer/feedback/details/467300/problem-with-varchar-max-via-sql-native-client).”
Have I done something wrong?
It crashes on the Select * from TableName execution

code

Sub Action()
If Not IsConnected Then
MessageDialog.Show(“Connect to the database first.”)
End If

DataList.RemoveAllRows

Var sql As String = “SELECT * FROM DRS_MASTER;” <<<<<<<<<<<<<<< my change
Var data As RowSet

try
data = mDB.SelectSQL(sql) <<<<<<<<<<<<<<<<<<<<< crashes here
Catch err as DatabaseException
MessageDialog.Show("DB Error: " + err.Message)
Return
End Try

If data <> Nil Then
For Each row As DatabaseRow In data
DataList.AddRow(row.ColumnAt(0).StringValue, row.ColumnAt(1).StringValue, _
row.ColumnAt(2).StringValue, row.ColumnAt(3).StringValue)
Next

data.Close

End If

End Sub

2

There is a bug in SQL Server Native client which is linked in the error message. If you follow the link you’ll see how to mitigate the issue.

This is not a bug in your code but how the Native client processes Varchar(Max) defined columns.

3

There are two problems when dealing with MS SQL Server Databases that relate to me.

  1. NVARCHAR(MAX) should be defines as NVARCHAR(4000) . If you actually want maximum length storage. Nothing yo stop you defining field as NVARCHAR(2000) for example if you want.

  2. This stores the value as in MS Access called YES/NO. MS SQL Server calls it (BIT null).
    My workaround for this will be to change all NIT definitions to a NVARCHAR(1) Text Field.

I will need to go through my database (all tables) and where I find a MAX or a BIT (The largest Textfield and the smallest data field) I will need to redefine these fields by using the following code:

SQL = " ALTER TABLE table_name ALTER COLUMN column_name datatype ;"

You are saying this problem has been around for a long time and MSoft is responsible for fixing the problem. How is it that I don’t have the problem when accessing the Database using VB6?

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