IBM 000-8697 Manual Do Utilizador

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IBM Informix OnLine Database Server Administrator’s Guide
Monitor Logging Activity
Execute the -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
index key 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.
Execute tbcheck -pl with a database name or a table name parameter to
obtain a listing of the index key values and the corresponding rowids for each
index leaf node page.
 illustrates a simple index structure.
Execute tbcheck -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
Monitor logging activity to determine the amount of total available space in
the logical log files and the available space in the current log file.
If the total free space in the logical log files is less than half of a single log file,
OnLine does not create an archive.
Figure 3-3
A simple index
structure
B+ Tree
Root node
Branch nodes
Leaf nodes
Pointer to data (rowids)