System Architecture 2-139
Structure of an Index Page
Whenthe byte value is followed by a rowid and two addresses, the index key
entryindicates that more than one data row shares the same byte value. The
twoaddresses are a range of pages. The first address specifies the node page
where the specified rowid (the first rowid with this key value) appears. The
second address points to the last node page that contains a rowid for this
same byte value.
One index key entry on the root node page contains only an address. That
dataslot is referred to as the infinity slot. The infinity slot always points to the
next level beneath, to the node that contains all values greater than the last
value stored at this current level.
In general, the far-right slot (the last one) of the far-right node at every
nonleaf level is an infinity slot.