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Sybase ADAPTIVE SERVER IQ 12.4.0 User Manual

Page 38

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38

To verify that the data is not corrupt and set the database storage to its actual
value, you start the server with the

-iqdroplks

switch and connect to the

database. You then set the option

dbcc_option

and run the

sp_iqcheckdb

stored procedure. Depending on results, you may need to reset this option and
rerun the procedure. See the discussion below for details.

New set option

A new set option, dbcc_option, controls the actions performed by

sp_iqcheckdb

. This option applies only to the database you are connected to

when you set the option.

dbcc_option option

Function

Overrides the default operation of

sp_iqcheckdb

Allowed values

0 - 3

Default

0

Description

The value of this option determines the processing that

sp_iqcheckdb

does.

Value

Action

0

Runs default action:

• If

-iqdroplks

was specified during server startup, runs

CheckStorage Fix

. Checks for leaked blocks and corrupt

database pages by walking all the block maps in the system and
reading every database page. If no error is detected, resets
database free list to calculated allocation map.
If an error is
found, it is reported in

.iqmsg

file, but free list is not altered.

• If

-iqdroplks

was not specified during server startup, runs

GatherStatistics

. Produces report. If severe error found,

server may terminate.

In this read-only mode,

sp_iqcheckdb

does not lock the

database to prevent other writers. Therefore, it may incorrectly
report that leaks were detected, because it did not see new
versions of objects outside its transactional scope.

1

Runs CheckAllocation. Checks for leaked blocks by walking all
block maps in the system. Runs very fast (about 1 second per GB
of data). Produces a report of findings. Does not reset the free list.

This option provides a fast method of determining if the database
has potentially leaked any storage.