<s>
Log	B-General_Concept
shipping	I-General_Concept
is	O
the	O
process	O
of	O
automating	O
the	O
backup	O
of	O
transaction	B-General_Concept
log	I-General_Concept
files	O
on	O
a	O
primary	O
(	O
production	O
)	O
database	O
server	O
,	O
and	O
then	O
restoring	O
them	O
onto	O
a	O
standby	O
server	O
.	O
</s>
<s>
This	O
technique	O
is	O
supported	O
by	O
Microsoft	B-Application
SQL	I-Application
Server	I-Application
,	O
4D	B-Language
Server	I-Language
,	O
MySQL	B-Application
,	O
and	O
PostgreSQL	B-Application
.	O
</s>
<s>
Similar	O
to	O
replication	B-Architecture
,	O
the	O
primary	O
purpose	O
of	O
log	B-General_Concept
shipping	I-General_Concept
is	O
to	O
increase	O
database	O
availability	O
by	O
maintaining	O
a	O
backup	O
server	O
that	O
can	O
replace	O
a	O
production	O
server	O
quickly	O
.	O
</s>
<s>
Other	O
databases	O
such	O
as	O
Adaptive	B-Application
Server	I-Application
Enterprise	I-Application
and	O
Oracle	B-General_Concept
Database	I-General_Concept
support	O
the	O
technique	O
but	O
require	O
the	O
Database	B-General_Concept
Administrator	I-General_Concept
to	O
write	O
code	O
or	O
scripts	O
to	O
perform	O
the	O
work	O
.	O
</s>
<s>
Although	O
the	O
actual	O
failover	B-General_Concept
mechanism	O
in	O
log	B-General_Concept
shipping	I-General_Concept
is	O
manual	O
,	O
this	O
implementation	O
is	O
often	O
chosen	O
due	O
to	O
its	O
low	O
cost	O
in	O
human	O
and	O
server	O
resources	O
,	O
and	O
ease	O
of	O
implementation	O
.	O
</s>
<s>
In	O
comparison	O
,	O
SQL	O
server	B-Architecture
clusters	I-Architecture
enable	O
automatic	O
failover	B-General_Concept
,	O
but	O
at	O
the	O
expense	O
of	O
much	O
higher	O
storage	O
costs	O
.	O
</s>
<s>
Compared	O
to	O
database	O
replication	B-Architecture
,	O
log	B-General_Concept
shipping	I-General_Concept
does	O
not	O
provide	O
as	O
much	O
in	O
terms	O
of	O
reporting	O
capabilities	O
,	O
but	O
backs	O
up	O
system	O
tables	O
along	O
with	O
data	O
tables	O
,	O
and	O
locks	O
the	O
standby	O
server	O
from	O
users	O
 '	O
modifications	O
.	O
</s>
<s>
views	O
)	O
and	O
is	O
therefore	O
unsuitable	O
for	O
failover	B-General_Concept
purposes	O
.	O
</s>
