>>>>>I have been tormented by this message for months. When two or more users start to use my invoice form, I get this error. I am on optimistic buffering mode (master - record buffering, detail - table buffering in grid). It happens occasionally when a user finishes one invoice (tableupdated) and is half way through the second invoice entry while another user is doing the same stuff.
>>>>>
>>>>>Anyone can suggest the possible cause of this problem?
>>>>
>>>>How do you add records to the table? How do you assign primary keys? Does your code contain any REPLACE FOR or REPLACE ALL statements?
>>>
>>>I use TASTRADE kind of NEWID to assign primary key (surrogated key). After APPEND BLANK in the master table, I use INSERT (key) VALUES (key) where key is the value obtained from master table. In grid, I use REPLACE key WITH master.key. I can't find any REPLACE ALL/FOR command in my form but I certainly have DELETE FOR EMPTY(xxxfield) (details table) before I do tableupdate. Do you think it matters?
>>
>>
>>Yes.
>>
>>There are a certain number of commands that place an
>>implicit file lock on the table. Replace all/for
>>and also Delete all/for are a couple of them. You might
>>try to find some other way to handle the deletion of records
>>with empty fields if you feel that is necessary. Such as
>>locate empty records within a do while loop and rlock with error
>>handling before deleting.
>>
>>But probably you need to use form validation with optimistic
>>buffering. The form validation will check for an empty in
>>these key fields and not call the save until whatever validation
>>you choose to put in there are satisfied.
>>
>>Hope this helps.
>>
>>Dan
>
>Thanks for the advice. But what do you mean by 'not call the save until whatever validation..'? I assume when you say 'form validation', you are saying validation in some controls. If this validation fails, I don't allow them to save. Do I get you right? If I get you right, I can't because there is nothing wrong with adding empty records.


Let me see if I get you right you are issuing a DELETE FOR
EMPTY(keyField) correct. When I first got started in foxpro just
fresh form DBASE IV, I used a lot of DELETE FOR's and REPLACE
FOR's. I had many problems with this "Record in user by another"
message. The advice given to me was "Don't use these unless
this is done as some type of night-time processing when there
is no chance of other users being on the system. If at some
point you need to get rid of these records, I would suggest an
alternative way. Don't add these empty records if you were going
to delete them anyways.

If you have a "Save" button on your form. Add a method to your
form "formValid" which checks for any number of things and
returns a false if it does not pass. One of these tests could
be checking for empty key fields. If the formValid method
returns a false, let the user know what's happening but do not
save this record.

Dan
:)

HTH