🚀 go-pugleaf

> this : ADOQuery1->Parameters->Items[0]->Value = NULL;
> ... 
> How can I insert data with NULL value ?

You need to be careful here. You need to distinguish carefully between NULL and
System::Null. System::Null is a constant that represents a null variant object. This
is what you want to assign to your parameter. NULL is very different. It is not a
variant. In C++, NULL is typically used to represent a nil pointer. NULL is usually
#defined to be 0, or to be a (void *)(0). 

The C++ version of NULL has nothing to do with databases or NULL fields in a table.
NULL in C++ is very different than NULL in database speak. If you assign NULL to a
field or parameter, you will probably end up with a field that contains the string
"0" or the number 0. If you want the field to be NULL in database terms, assign it a
value of System::Null in code.

Harold Howe [TeamB]
http://www.bcbdev.com