I create a CA based on ADO to connect to SQL Server DB
Here the Select CMD:

SELECT Firms.name, Clients.Id, Clients.Phone FROM Clients LEFT OUTER JOIN Firms ON Clients.Firm = Firms.Id

Field Name is not marked as Updatable or Key Field

Firms has CONSTRAIN index to other tables, when I DELETE IN CA TableUpdate() gives me a error:
1435
Microsoft OLE DB Provider for SQL Server : DELETE statement conflicted with COLUMN REFERENCE constraint 'FK_phones_Firms'. The conflict occurred in database 'task', table 'phones', column 'firm'.

but I don't want to delete the firm, I want just to remove it from Clients table, why CA try to delete the record in Firms?
How can I delete a record in Clients w/o CA delete the record in Firms?
By the way when I refresh Coursor After Error The record is removed.

TIA