>>>>So, how do you want to solve this problem? You can also make this textbox invisible in case of empty if that's what you meant by hiding.
>>>
>>>I will let you know if and when I find the solution to this.
>>
>>Can you explain exactly what you're trying to achieve? What is your front-end application?
>
>Only if you promise not to bombard me with suggestions <g>
>
>Here it is in a simplified description.
>
>Parent table: Look up for various references. This table has 3 columns:
>1 - PK (Identity)
>2 - AK (Candidate/Unique field) field REFERENCE (char 10). Examples: MAILED, FAXED, EMAILED.
>3 - Description field (DESCRIPTION char(50)). Description of the value in the REFERENCE field.
>
>Child table: Has FK field REFERENCE. User selects entry from a look up or enters value manually. For RI the value user enters has to be in the field REFERENCE of Parent table.
>Sometimes, user wants to blank (delete the entry) from the child table (for whatever reason). If he/she does it and saves the record, the RI constraint will not let them.
>
>So I would need to have a record/row in the Parent table with the value in field/column REFERENCE blank.
>
>That's all.

Dmitry,

This is how I would solve it.

Don't add empty record to the Parent table.

When the user deletes a value in the reference field, convert it to NULL behind the scenes (when it's time to save).

That's all what is needed, IMHO.