<s>
RDM	B-Application
Server	I-Application
is	O
an	O
embeddable	O
,	O
heterogeneous	O
,	O
client/server	B-Operating_System
database	B-General_Concept
management	I-General_Concept
system	I-General_Concept
supporting	O
both	O
C/C	O
++	O
and	O
SQL	B-Language
APIs	B-General_Concept
for	O
programming	O
flexibility	O
.	O
</s>
<s>
The	O
databases	O
can	O
be	O
disk	O
resident	O
and/or	O
memory	B-General_Concept
resident	O
.	O
</s>
<s>
RDM	B-Application
Server	I-Application
implements	O
multi-user	O
locking	O
,	O
hot	O
database	O
backup	O
,	O
and	O
a	O
fully	O
ACID-compliant	O
transaction	O
logging	O
system	O
with	O
automatic	O
crash	O
recovery	O
.	O
</s>
<s>
The	O
database	O
library	O
can	O
optionally	O
be	O
run	O
in-process	O
with	O
the	O
application	O
,	O
eliminating	O
client/server	B-Operating_System
remote	B-Operating_System
procedure	I-Operating_System
calls	I-Operating_System
.	O
</s>
<s>
RDM	B-Application
Server	I-Application
was	O
first	O
released	O
in	O
1993	O
as	O
an	O
NLM	B-Application
for	O
the	O
NetWare	B-Operating_System
platform	O
under	O
the	O
name	O
RDS	O
(	O
Raima	O
Database	O
Server	O
)	O
.	O
</s>
<s>
It	O
was	O
derived	O
from	O
its	O
predecessor	O
Raima	B-Application
Database	I-Application
Manager	I-Application
,	O
and	O
subsequently	O
renamed	O
Velocis	O
.	O
</s>
<s>
The	O
database	O
is	O
currently	O
known	O
by	O
the	O
name	O
RDM	B-Application
Server	I-Application
,	O
and	O
is	O
currently	O
offered	O
as	O
version	O
8.4	O
.	O
</s>
<s>
RDM	B-Application
Server	I-Application
is	O
a	O
client/server	B-Operating_System
database	O
engine	O
with	O
an	O
optional	O
configuration	O
to	O
execute	O
the	O
engine	O
in-process	O
with	O
the	O
application	O
.	O
</s>
<s>
When	O
in	O
a	O
client/server	B-Operating_System
configuration	O
,	O
clients	O
perform	O
remote	B-Operating_System
procedure	I-Operating_System
calls	I-Operating_System
(	O
RPC	B-Operating_System
)	O
to	O
a	O
server	O
on	O
the	O
same	O
computer	O
or	O
a	O
computer	O
that	O
is	O
visible	O
across	O
a	O
network	O
.	O
</s>
<s>
Since	O
its	O
first	O
release	O
in	O
1993	O
,	O
RDM	B-Application
Server	I-Application
has	O
allowed	O
user-defined	O
code	O
to	O
be	O
loaded	O
dynamically	O
into	O
the	O
server	O
process	O
as	O
a	O
DLL	O
or	O
shared	O
library	O
.	O
</s>
<s>
This	O
technology	O
was	O
termed	O
extension	O
modules	O
and	O
was	O
also	O
used	O
as	O
the	O
mechanism	O
for	O
advanced	O
functional	O
modules	O
such	O
as	O
Raima	O
's	O
SQL	B-Language
.	O
</s>
<s>
The	O
RDM	B-Application
Server	I-Application
core	O
engine	O
is	O
a	O
derivative	O
of	O
Raima	B-Application
Database	I-Application
Manager	I-Application
,	O
which	O
had	O
been	O
released	O
9	O
years	O
earlier	O
.	O
</s>
<s>
As	O
a	O
derivative	O
product	O
,	O
the	O
native	O
API	B-General_Concept
is	O
a	O
low-level	O
C/C	O
++	O
API	B-General_Concept
.	O
</s>
<s>
The	O
native	O
C	B-Language
API	B-General_Concept
is	O
an	O
extensive	O
library	O
functions	O
for	O
all	O
database	O
operations	O
.	O
</s>
<s>
This	O
facility	O
is	O
also	O
used	O
for	O
asynchronous	B-Architecture
replication	B-Architecture
.	O
</s>
<s>
RDM	B-Application
Server	I-Application
supports	O
regular	O
B-tree	B-Architecture
based	O
indexes	O
.	O
</s>
<s>
Databases	O
can	O
be	O
disk	O
resident	O
,	O
memory	B-General_Concept
resident	O
or	O
a	O
hybrid	O
.	O
</s>
<s>
In	O
the	O
first	O
case	O
,	O
all	O
access	O
to	O
disk	O
resident	O
structures	O
(	O
both	O
data	O
or	O
data	O
index	O
information	O
)	O
,	O
happens	O
through	O
an	O
in-memory	B-General_Concept
data	O
cache	O
maintained	O
by	O
the	O
database	O
server	O
sub-system	O
.	O
</s>
<s>
Alternatively	O
,	O
the	O
application	O
can	O
define	O
database	O
structures	O
to	O
reside	O
in	O
memory	B-General_Concept
.	O
</s>
<s>
An	O
application	O
can	O
also	O
define	O
a	O
database	O
with	O
mixed	O
disk-based	O
or	O
memory-resident	O
data	O
structures	O
.	O
</s>
<s>
The	O
data	B-Language
definition	I-Language
language	I-Language
of	O
the	O
engine	O
supports	O
mixing	O
different	O
storage	O
types	O
for	O
any	O
data	O
structure	O
.	O
</s>
<s>
RDM	B-Application
Server	I-Application
supports	O
the	O
following	O
native	O
data	O
types	O
:	O
signed	O
and	O
unsigned	O
8-	O
,	O
16-	O
,	O
32	O
-	O
and	O
64-bit	O
integers	O
,	O
UTF-8	O
and	O
Unicode	O
characters	O
,	O
floating	O
point	O
(	O
32	O
and	O
64	O
bit	O
)	O
,	O
BLOBs	B-General_Concept
(	O
binary	B-General_Concept
large	I-General_Concept
objects	I-General_Concept
)	O
,	O
BCD	O
(	O
Binary	O
Coded	O
Decimal	O
)	O
,	O
date	O
,	O
time	O
and	O
timestamp	O
.	O
</s>
<s>
The	O
product	O
offers	O
two	O
data	B-Application
models	I-Application
.	O
</s>
<s>
The	O
network	B-General_Concept
data	I-General_Concept
model	I-General_Concept
manages	O
relationships	O
between	O
data	O
objects	O
through	O
list	O
of	O
pointers	O
called	O
sets	O
.	O
</s>
<s>
The	O
network	B-General_Concept
model	I-General_Concept
is	O
defined	O
to	O
allow	O
very	O
flexible	O
relationships	O
between	O
objects	O
.	O
</s>
<s>
A	O
hierarchical	O
structure	O
has	O
parent-child	O
relationships	O
;	O
the	O
network	B-General_Concept
model	I-General_Concept
allows	O
for	O
the	O
same	O
structure	O
except	O
there	O
is	O
no	O
limitation	O
on	O
the	O
number	O
of	O
parents	O
a	O
child	O
has	O
.	O
</s>
<s>
The	O
relational	B-Architecture
data	I-Architecture
model	I-Architecture
manages	O
relationships	O
between	O
data	O
objects	O
through	O
value	O
matching	O
,	O
and	O
usually	O
primary	O
key/foreign	O
keys	O
.	O
</s>
<s>
RDM	B-Application
Server	I-Application
allows	O
for	O
mixing	O
both	O
the	O
network	B-General_Concept
model	I-General_Concept
and	O
relational	B-Architecture
model	I-Architecture
in	O
the	O
same	O
database	O
definition	O
giving	O
the	O
application	O
developer	O
additional	O
flexibility	O
.	O
</s>
<s>
Extension	O
modules	O
that	O
are	O
automatically	O
available	O
in	O
RDM	B-Application
Server	I-Application
include	O
:	O
</s>
<s>
Raima	O
's	O
SQL	B-Language
is	O
an	O
extension	O
that	O
implements	O
ANSI	O
SQL	B-Language
based	O
on	O
the	O
1989	O
and	O
1992	O
standards	O
.	O
</s>
<s>
It	O
supports	O
the	O
following	O
SQL	B-Language
data	O
types	O
:	O
char	O
,	O
varchar	O
,	O
long	O
varchar	O
,	O
smallint	O
,	O
integer	O
,	O
bigint	O
,	O
wchar	O
(	O
Unicode	O
)	O
,	O
wvarchar	O
,	O
long	O
wvarchar	O
,	O
float	O
,	O
double	O
,	O
real	O
,	O
decimal/numeric	O
,	O
date	O
,	O
time	O
,	O
timestamp	O
,	O
rowid	O
,	O
binary	O
,	O
varbianary	O
,	O
long	O
varbinary	O
,	O
and	O
c_data	O
(	O
read	O
access	O
to	O
native	O
array	O
and	O
struct	O
data	O
types	O
)	O
.	O
</s>
<s>
The	O
SQL	B-Language
API	B-General_Concept
is	O
implemented	O
as	O
a	O
SAG	O
CLI	O
interface	O
giving	O
access	O
to	O
the	O
supported	O
SQL92	B-Language
standard	O
.	O
</s>
<s>
RDM	B-Application
Server	I-Application
has	O
full	O
support	O
for	O
ODBC	O
v3.51	O
,	O
JDBC	O
v3	O
and	O
v4	O
through	O
a	O
Java	O
type	O
4	O
implementation	O
,	O
ADO.Net	O
and	O
even	O
PHP	O
.	O
</s>
<s>
Active	O
and	O
passive	O
replication	B-Architecture
is	O
also	O
available	O
,	O
maintaining	O
an	O
identical	O
copy	O
of	O
a	O
master	O
database	O
for	O
application	O
failover	O
.	O
</s>
<s>
The	O
subsystem	O
implements	O
an	O
asynchronous	B-Architecture
single	O
master	O
multi-slave	O
replication	B-Architecture
engine	O
based	O
on	O
its	O
supporting	O
client	B-Operating_System
–	I-Operating_System
server	I-Operating_System
transports	O
(	O
including	O
TCP/IP	B-Protocol
)	O
.	O
</s>
<s>
Administrative	O
functions	O
allow	O
RDM	B-Application
Server	I-Application
to	O
be	O
placed	O
into	O
a	O
hot	O
backup	O
mode	O
so	O
that	O
database	O
files	O
can	O
be	O
safely	O
copied	O
to	O
another	O
permanent	O
media	O
.	O
</s>
<s>
The	O
product	O
is	O
available	O
both	O
as	O
object	O
code	O
and	O
as	O
source	O
code	O
,	O
and	O
currently	O
supports	O
the	O
following	O
target	O
platforms	O
:	O
AIX	B-Application
,	O
FreeBSD	B-Operating_System
,	O
HPUX	B-Application
,	O
Linux	B-Application
(	O
Red	O
Hat	O
Enterprise	O
,	O
and	O
Ubuntu	O
)	O
,	O
MAC	B-Application
OS	I-Application
,	O
QNX	O
Neutrino	O
,	O
Solaris	B-Application
and	O
Windows	O
.	O
</s>
<s>
RDM	B-Application
Server	I-Application
is	O
today	O
used	O
in	O
a	O
wide	O
range	O
of	O
applications	O
for	O
business	O
critical	O
data	O
transactions	O
,	O
flight	O
control	O
systems	O
,	O
medical	O
equipment	O
,	O
network	O
management	O
systems	O
and	O
more	O
.	O
</s>
