I have a C application that caches data from some database tables.
The tables have a trigger that update the row with a generator id
whenever the row changes. Every time the cache is refreshed from
tables to memory, the last id read is kept track of. Next time, the
cache is refreshed, to avoid reading the entire dataset, only the rows
having id greater than the last id are read. The problem with this
is that after the cache is refreshed, a transaction with a lower
generator id might commit and the caching scheme will miss this row.

Maybe this is not a good way to do this. Anyone has other suggestions ?

Thanks!

--- In firebird-support@yahoogroups.com, "Alan McDonald" <alan@m...>
wrote:

>
> > I am using this to keep track of changes so that they can be cached
> > for example in an application. To do this, it's easy to select all the
> > rows that have the id greater than the id I saw last time.
> > Therefore I need to know if any transaction with a lower id might now
> > commit in the future.
> >
> > Thanks!
>
> since generators are fired outside transaction control there is no
> relationship here (necessarily)...
> Tell us what component set you are using and a little more about

what this

> caching is all about and someone may have some suggestions for you.
> you talk about a lower id commiting but also about selecting higher

ids so I

> can't quite follow.
> But there is already some very good caching going on in some component
> sets..
> tell us more about the size of the datasets you are experiencing,

whether

> local or remote connections etc
> Alan
>
>
> >
> > --- In firebird-support@yahoogroups.com, "Alan McDonald" <alan@m...>
> > wrote:
> > >
> > > >
> > > > Is there any way to find out if there are any uncommitted
> > transactions
> > > > that have called gen_id on a generator ?
> > > > Or if I get an id using the gen_id call, can I somehow wait till
> > all
> > > > current transactions either commit or abort ?
> > > >
> > > > Thanks!
> > > >
> > >
> > > uh oh... what are you trying to do... sounds fishy
> > > Alan
> > >
>