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TADOTable Field.Required property

When TADOTable object connected to SQL Database table. I noticed that the Field.Required and FieldDef.Required property always returns False, even though the underlying Table has field which is non Nullable.

Is it because of the MDAC version or SQL server version conflict ? I search every where on the web but could not find any one mentioned about having this problem.

I am using XP machine to connect to SQL Sever 2000 which is running in window 2000 server.

Your help will be very much appreciated.

Cheers,

nctran

Ivanov_G

Delphi help says :

If a field is created with the Fields editor, then this property is set based on the underlying table. Applications that set Required to True for fields that must have values (for example, a password or part number), but for which the underlying table does not require the field, must write an OnValidate event handler to enforce the property.

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Mohammed Nasman

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Ivanov_G

whenever possible - use direct access components :P)

http://crlab.com/sdac/

I am using them and everything is OK :)))

nctran

ASKER

SQL database table has specified the field is required (non Nullable). But when loaded into TADOTable the field.Required property is always return false.

any ideas ?

Best Regards

Mohammed Nasman

Hello

Here's a better way, without modifying Delphi sources

procedure TForm1.Button1Click(Sender: TObject);
var
ReqField : Integer;
const
adFldIsNullable = $00000020;
begin
if (AdoTable1.Recordset.Fields[1].attributes and adFldIsNullable) = 0 then
ShowMessage(AdoTable1.Recordset.Fields[1].Name + ' is Required Field')
else
ShowMessage(AdoTable1.Recordset.Fields[1].Name + ' not Required Field')

end;

Regards,
Mohammed

Ivanov_G

Set Debug DCU in Project / Options / Compiler / Debugging and step inside the ado units to see why it fails ...

nctran

ASKER

Thanks Mohammed,
I knew it was a bug in ADO express but not quite sure where is a good place to fix it. Because I Trace through the code and found that the attributes never get check again adFldNullable.

It seems to work for SQL database .But I don't know if there is any problem when connected TADOTable object to any other databases and I hope not.

I prefer to change it in the ADODB because It saves me to go everywhere in my code to change Field.Required to Recordset.Field[i].Attributes and adFldIsNullable = 0

So I will accept your comment.

Thank you.