3-80 IBM Informix OnLine Database Server Administrator’s Guide

Monitor Logging Activity

Executethe -pk or -pK options of tbcheck to obtain all page information. (The
mnemonic-k option refers to “keep all” information.) Execute tbcheck -pk
with a database name or a table name parameter to obtain a listing of the
indexkey values and the corresponding rowids for each index leaf page. Also
listed is the node page to which each leaf page is joined.
Execute the -pl or-pL options of tbcheck to obtain leaf node information.
Executetbcheck -pl with a database name or a table name parameter to
obtaina listing of the index key values and the corresponding rowids for each
index leaf node page.Figure 3-3 illustrates a simple index structure.
Executetbcheck -pc with a database name parameter to obtain the following
specific index information organized by table:
■Number of indexes
■Data record size
■Index record size
■Number of records
Monitor Logging Activity
Monitorlogging activity to determine the amount of total available space in
the logical log files and the available space in the current log file.
Ifthe total free space in the logical log files is less than half of a single log file,
OnLine does not create an archive.
Figure3-3
A simple index
structure
B+ Tree Root node
Branch nodes
Leaf nodes
Pointer to data (rowids)