Sybase ADAPTIVE SERVER IQ 12.4.0 User Manual
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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.
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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.