Sybase ADAPTIVE SERVER IQ 12.4.0 User Manual

Page 37

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37

Incremental backups are disabled

After the database is opened in

forced recovery mode, incremental backups are disabled. The next backup
must be a full backup. Doing a full backup reenables incrementals.

Forced recovery affects all databases opened

The forced recovery

parameter applies to all opens of the database while the server is up.
Therefore, after the database is opened, the DBA needs to bring the server
back down, and then restart the server without the forced recovery flag, to
be sure that subsequent opens run in regular mode. Repeated opens of the
database with forced recovery on do not harm the database, but could be
confusing to the DBA because each forced recovery open marks all the
storage within the database as in use.

Use the -gd switch during forced recovery.

Sybase recommends that

you start the IQ server with the

-gd

switch set to restrict access to the

server to the DBA. Forced recovery operates in all modes, but restricted
access gives the DBA greater control over inadvertent opens of the
database.

Leaked space
recovery

Either through system failure or as a result of opening a database with forced
recovery, a database’s allocation map may not reflect the true allocation of its
usage. When this occurs, we say that it has “leaked” storage. Adaptive Server
IQ 12.4.0 resolves this problem by adding the ability to recover leaked storage.

When leaked storage is being recovered, other transactions that alter the
allocation map are shut out. Such operations include checkpoints, and
commands that modify the database.

Two new server startup parameters,

-iqfrec

and

-iqdroplks

, and one additional

run-time setting,

dbcc_option

, support the new forced recovery and leaked

storage recovery feature.

New server startup
parameters

The following table describes the new server startup parameters.

Parameter

Scope

Description

-iqfrec

dbname

database

Marks the specified
database as in use and
restores database to its last
known consistent state.

-iqdroplks

dbname

database

Allows the

sp_iqcheckdb

stored procedure to recover
leaked storage within the
specified database.

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