Android Question DBRequestManager problem passing null uniqueidentifier to SQL Server

[Frank Cazabon]

I am using DBRequestManager to send data from a SQLite database on my tablet to a SQL Server on a Windows server. My code is failing with this error:

java.sql.SQLException: Conversion failed when converting from a character string to uniqueidentifier.

The error occurs when I try to send a Null value to a uniqueidentifier field that is set to allow nulls.

This should work, shouldn't it? Or do I need to do something special with Nulls in order to pass them?

 

[Frank Cazabon]

Hmm... with some more investigation it seems that the expected value is "null" not null! This would explain the error, but why would a null get stored as a character string in SQLite?

The code that I use to populate the sqlite table is this:

    Dim dispositionPK As String
    If chkDelivered.Checked = False Then
        dispositionPK = dispositionMap.Get(spnDisposition.SelectedItem)
    Else
        dispositionPK = Null
    End If
   
    m.Put("del_dspfk", dispositionPK)

    DBUtils.InsertMaps(SQLLite, "DeliveryHistory", ListOfMaps)

How can I add a null value in? Should I change the code to this instead?

    Dim dispositionPK As String
    If chkDelivered.Checked = False Then
        dispositionPK = dispositionMap.Get(spnDisposition.SelectedItem)
        m.Put("del_dspfk", dispositionPK)
    End If
   
    DBUtils.InsertMaps(SQLLite, "DeliveryHistory", ListOfMaps)

 

[keirS]

I suspect the problem is in DBUtils not dealing with nulls correctly. Try building your own string and use ExecNonQuery and use the SQLite NULL keyword.

Dim sInsertSring As String
sInsertSring = 'INSERT INTO DeliveryHistory (del_dspfk) VALUES (NULL)'

 

[Frank Cazabon]

Thanks, changing my code where I just don't issue a Put on the map for this key works.

I suspect doing this would also work:

m.Put("del_dspfk", Null)

As I have code similar to that elsewhere, but maybe there is a problem with DBUtils converting a variable with a null value, or maybe there's something wrong with my code assigning the Null value to the variable.

 

[Erel]

Change dispositionPK type to Object. When you assign Null to string it is converted to "null".

 

[Frank Cazabon]

Change dispositionPK type to Object. When you assign Null to string it is converted to "null".

thanks. Is it only Objects that can be assigned Null? Or can I set Null to Doubles and other types?

 

[Erel]

You can assign null to any type except of the numeric types, boolean and String.

 

[Frank Cazabon]

Thanks

 

[Roberto P.]

Hello, someone can tell me that Oedipus to Get to the field of type "uniqueidentifier"
sField = aRecord.GetDouble ("UniqueField")
thanks

 

[Frank Cazabon]

Hello, someone can tell me that Oedipus to Get to the field of type "uniqueidentifier"
sField = aRecord.GetDouble ("UniqueField")
thanks

I think auto correct must have done something to what you meant to type. Could you ask again, please?

 

[Roberto P.]

Hello,
I just solved:

if the data type uniqueidentifier to read data from the DB to use:

aCursor.GetString ("FieldName")
I hope it is useful to others