IBM 000-8697 User Manual
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IBM Informix OnLine Database Server Administrator’s Guide
tbcheck -pB and tbcheck -pe Utility Commands
Refer to
for tbcheck -pB and tbcheck -pe syntax information.
The tbcheck -pB command displays statistics that describe the average
fullness of blobpages. These statistics provide a measure of storage efficiency
for individual blobs in a database or table. If you find that the statistics for a
significant number of blobs show a low percentage of fullness, OnLine might
benefit from resizing the blobpage in the blobspace.
fullness of blobpages. These statistics provide a measure of storage efficiency
for individual blobs in a database or table. If you find that the statistics for a
significant number of blobs show a low percentage of fullness, OnLine might
benefit from resizing the blobpage in the blobspace.
The following example retrieves storage information for all blobs stored in
the table sriram.catalog in the stores5 database:
the table sriram.catalog in the stores5 database:
tbcheck -pB stores5:sriram.catalog
shows the output of this command.
Space Name
is the name of the blobspace that contains one or more blobs
stored as part of the table (or database).
Page Number
is the starting address in the blobspace of a specific blob.
Pages
is the number of OnLine pages required to store this blob.
Percent Full
is a measure of the average fullness of all the blobpages that
hold this blob.
Page Size
is the size in bytes of the blobpage for this blobspace. (Blobpage
size is always a multiple of the OnLine page size.)
Figure 5-1
Blobspace
usage
report
from
tbcheck -pB
BLOBSpace Report for stores5:sriram.catalog
Total pages used by table
7
BLOBSpace usage:
Space
Page
Percent Full
Name
Number
Pages
0-25%
26-50%
51-75%
76-100%
------------------------------------------------------------------
blobPIC
0x300080
1
x
blobPIC
0x300082
2
x
------
Page Size is 6144
3
bspc1
0x2000b2
2
x
bspc1
0x2000b6
2
x
------
Page Size is 2048
4