Doug

> But I am still a little confused on what would set a group 
> lock (I understand the record locks) and why a group lock 
> would need to be set and does it lock the entire file?
> 
A group in a file contains pointers between records and pointers to overflow
groups. So the group lock is there to ensure that no process can be changing
those pointers whilst another is coming along trying to eiterh read through
them or to write to the group. By doing this at the group level it means
that file integrity is perserved whilst at the same time ensuring that
multiple processes can still write (different groups within) the file at the
same time. So no, the whole file is not locked.

It's another reason to keep files well sized though since the group lock is
set on the primary group, so if you have long overflow chains that increases
contention on the lock table.

Brian 
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