Table I/O

One of the most frequent functions that the database server performs is to bring data and index pages from disk into memory. Pages can be read individually for brief transactions and sequentially for some queries. You can configure the number of pages that the database server brings into memory, and you can configure the timing of I/O requests for sequential scans.

You can also indicate how the database server is to respond when a query requests data from a dbspace that is temporarily unavailable.

The following sections describe these methods of reading pages.

For information about I/O for smart large objects, see Factors that affect I/O for smart large objects.