I doesn't realized postgresql can be such clever. Another problem I just found is after one tuple is deleted, there will be some slots unoccupied. The offset cannot be computed even know how much tuples a page can contain.
I need one hash table. Thanks -- Pei On Tue, Sep 21, 2010 at 8:47 PM, Kevin Grittner <kevin.gritt...@wicourts.gov > wrote: > Pei He wrote: > > > The offset is the order of a tuple in a Sequential Scan. > > That's not a safe assumption. Try starting a sequential scan against > a large table on one connection; then before it finishes, start the > same query on another connection. The second query joins the one > already in progress and then starts over, "wrapping around". > > -Kevin >
