<s>
The	O
OS	B-Operating_System
2200	I-Operating_System
database	O
managers	O
are	O
all	O
part	O
of	O
the	O
Universal	O
Data	O
System	O
(	O
UDS	O
)	O
.	O
</s>
<s>
Flat	O
files	O
(	O
sequential	O
,	O
multi-keyed	O
indexed	O
sequential	O
–	O
MSAM	O
,	O
and	O
fixed-block	O
)	O
,	O
network	B-General_Concept
(	O
DMS	O
)	O
,	O
and	O
relational	B-Application
(	O
RDMS	O
)	O
data	O
models	O
all	O
share	O
a	O
common	O
locking	O
,	O
recovery	O
,	O
and	O
clustering	O
mechanism	O
.	O
</s>
<s>
OS	B-Operating_System
2200	I-Operating_System
applications	O
can	O
use	O
any	O
mixtures	O
of	O
these	O
data	O
models	O
along	O
with	O
the	O
high-volume	O
transaction	O
file	O
system	O
within	O
the	O
same	O
program	O
while	O
retaining	O
a	O
single	O
common	O
recovery	O
mechanism	O
.	O
</s>
<s>
This	O
commonality	O
has	O
made	O
it	O
possible	O
for	O
clients	O
to	O
modernize	O
applications	O
moving	O
from	O
language	O
files	O
,	O
to	O
a	O
network	B-General_Concept
database	I-General_Concept
,	O
to	O
a	O
relational	B-Application
database	I-Application
.	O
</s>
<s>
In	O
OS	B-Operating_System
2200	I-Operating_System
locking	O
is	O
generally	O
implicit	O
in	O
the	O
database	O
verbs	O
used	O
.	O
</s>
<s>
The	O
database	O
managers	O
support	O
access	O
using	O
many	O
common	O
distributed	O
data	O
access	O
protocols	O
and	O
APIs	O
including	O
JDBC	B-Language
,	O
OLE	B-Language
DB	I-Language
,	O
and	O
ODBC	B-Application
.	O
</s>
<s>
See	O
also	O
Unisys	B-Application
OS	I-Application
2200	I-Application
distributed	I-Application
processing	I-Application
.	O
</s>
<s>
All	O
activity	O
in	O
all	O
of	O
these	O
areas	O
is	O
journaled	B-General_Concept
(	O
written	O
to	O
the	O
audit	O
trail	O
)	O
.	O
</s>
