09-13-2012
POSIX message queues persist over crash/reboot, until mq_unlink is called. They can be re-opened in the state they were. They are implemented as files without file semantics.
The only thing that CAN persist over a crash/reboot is a physical object - like bytes on a disk, flash disk, tape, etc.
SYSV and POSIX IPC objects are kernel persistent. They survive a program crash.
Not a system crash or reboot.
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LEARN ABOUT DEBIAN
apache::session::store::oracle
Apache::Session::Store::Oracle(3pm) User Contributed Perl Documentation Apache::Session::Store::Oracle(3pm)
NAME
Apache::Session::Store::Oracle - Store persistent data in a Oracle database
SYNOPSIS
use Apache::Session::Store::Oracle;
my $store = new Apache::Session::Store::Oracle;
$store->insert($ref);
$store->update($ref);
$store->materialize($ref);
$store->remove($ref);
DESCRIPTION
Apache::Session::Store::Oracle fulfills the storage interface of Apache::Session. Session data is stored in a Oracle database.
SCHEMA
To use this module, you will need at least these columns in a table called 'sessions':
id varchar2(32) # or however long your session IDs are.
a_session long
To create this schema, you can execute this command using the sqlplus program:
CREATE TABLE sessions (
id varchar2(32) not null primary key,
a_session long
);
If you use some other command, ensure that there is a unique index on the table's id column.
CONFIGURATION
The module must know what datasource, username, and password to use when connecting to the database. These values can be set using the
options hash (see Apache::Session documentation). The options are DataSource, UserName, and Password.
Example:
tie %hash, 'Apache::Session::Oracle', $id, {
DataSource => 'dbi:Oracle:database',
UserName => 'database_user',
Password => 'K00l'
};
Instead, you may pass in an already-opened DBI handle to your database.
tie %hash, 'Apache::Session::Oracle', $id, {
Handle => $dbh
};
The last option is LongReadLen, which specifies the maximum size of the session object. If not supplied, the default maximum size is 8 KB.
AUTHOR
This modules was written by Jeffrey William Baker <jwbaker@acm.org>
A fix for the commit policy was contributed by Michael Schout <mschout@gkg.net>
SEE ALSO
Apache::Session, Apache::Session::Store::DBI
perl v5.10.1 2010-10-18 Apache::Session::Store::Oracle(3pm)