>>>I have a Form class in which are two tables loaded (PARENTTABLE and CHILDTABLE).
>>>
>>>PARENTTABLE and CHILDTABLE are linked with CID_PARENT field in PARENTTABLE.
>>>
>>>When I want to do:
>>>
>>>SELECT childtable
>>>APPEND BLANK
>>>
>>>VFP 8.0 shows:
>>>Cannot write to the record because it is in use (Error 1502).
>>>
>>>I don't understand why?
>>>
>>>I have discovered that when in DataEnvironment I delete Relation object between those two tables error disapear, but I need that Relation.
>>
>>Do you have a referential integrity trigger on the child table for the foreign key? If so, could use INSERT - SQL and do something like:
>>

INSERT INTO ChildTable (ParentID) VALUES (ParentTable.ParentID)

>
>No, I don't have referential integrity.

Have you simplified the situation to figure out where, exactly the problem is? For example, did you create a plain form, add the two tables, add the relation, then try to append blank with, say just a click of a button?