Subject Re: [ib-support] Child Tables Problem Revisited
Author Svein Erling Tysvær
Hi Bill,

>Now, the situation is still the same. I can sometimes read in the first
>record of child, but on certain systems after a certain number of records it
>fails to return. Even worst is the following :

This just sounds strange, and I don't think anyone can tell you the reason
unless you give us a lot more information. Are you certain that it should
return more records? You are familiar with transactions, aren't you?
Records added within other transactions since the start of the transaction
that contains your DML should be invisible.

>My application is constantly adding records to the end, and deleting records
>from the front (to keep the database from overflowing available disk space).
>Unfortunately, even though the parents are being deleted, the childs are not
>releasing the space they contain to be reused. Thus the database continues
>to grow until it wanders off the end of the drive and corrupts.

Well, I don't think IB release space unless you do a backup/restore or
something, but it should reuse it. What may prevent IB from reusing space,
is long-running transactions. If an old transaction exists, IB cannot reuse
space from records deleted since that transaction started - simply because
that transaction should treat those records as existing (unless the delete
happened in that very transaction).