Boolean fields in DBAdvGrid


I have a problem with boolean fields in a TAdvDBGrid and even after having read the doc, I still can't find how to
make them work with a dataset from a SQL query.

When when my datasource is a Table, the TAdvDBGrid works perfetly : I can click and unclick 
on the boolean fields, no problem.

BUT when my datasource comes from a TQuery, then it doesn't work.

I got the message (in French) "impossible to update a read only Dataset"

So I added this to my code, so that my dataset is in edit mode but it still doesn't work :

MyDatamodule.ABSQuery.SQL.Text := MySQLquery;

// added code

Help would be appreciated a lot.

Thanks in advance.

Just to mention that the problem comes with the checkboxes.

I have
goEditing = true in grid.Options
Columns are NOT read only

Cannot be reproduced.
Test app:

Thanks for your answer. 

I had tested and just have test your example with the ADO connection : in all cases, works like a charm.
BUT i can't make it work with the absolute database driver. 

May I please send you a small example by email ? ( I'm a registered user)

Thanks in advance for your help.

Thanks for your answer. I've done others many tests and now I can make it work with a simple example. 

I will investigate more to try to understand where in my SQL code I get problems. Anyway thank you very much for your answer.

I'd also suggest to check with a standalone standard VCL TDBCheckBox connected to this boolean field.