<s>
In	O
computing	O
,	O
the	O
Oracle	B-Application
Call	I-Application
Interface	I-Application
(	O
OCI	O
)	O
consists	O
of	O
a	O
set	O
of	O
C-language	O
software	B-Application
APIs	I-Application
which	O
provide	O
an	O
interface	O
to	O
the	O
Oracle	B-General_Concept
database	I-General_Concept
.	O
</s>
<s>
OCI	O
offers	O
a	O
procedural	O
API	B-Application
for	O
not	O
only	O
performing	O
certain	O
database	O
administration	O
tasks	O
(	O
such	O
as	O
system	O
startup	O
and	O
shutdown	O
)	O
,	O
but	O
also	O
for	O
using	O
PL/SQL	B-Language
or	O
SQL	B-Language
to	O
query	O
,	O
access	O
,	O
and	O
manipulate	O
data	O
.	O
</s>
<s>
The	O
OCI	O
library	B-Library
,	O
based	O
on	O
Oracle	B-Application
's	O
undocumented	O
User	B-Application
Programmatic	I-Application
Interface	I-Application
(	O
UPI	O
)	O
,	O
acts	O
as	O
an	O
"	O
interpreter	O
"	O
between	O
applications	O
and	O
the	O
low-level	O
database	O
network	O
protocol	O
.	O
</s>
<s>
Oracle	B-Application
Corporation	I-Application
first	O
released	O
OCI	O
(	O
under	O
the	O
name	O
HLI	O
,	O
the	O
Host	O
Language	O
Interface	O
)	O
with	O
Oracle	B-General_Concept
Database	I-General_Concept
version	O
6	O
in	O
1988	O
.	O
</s>
<s>
For	O
example	O
,	O
the	O
rollback	B-Application
statement	O
:	O
the	O
call	O
upirol	O
in	O
UPI	O
became	O
orol	O
in	O
OCI	O
.	O
</s>
<s>
Later	O
,	O
in	O
Oracle8	B-General_Concept
(	O
released	O
in	O
1997	O
)	O
,	O
OCI	O
calls	O
acquired	O
more	O
descriptive	O
names	O
;	O
orol	O
became	O
OCITransRollback	O
.	O
</s>
<s>
Oracle	B-Application
Corporation	I-Application
claims	O
that	O
OCI	O
is	O
"	O
So	O
reliable	O
that	O
every	O
SQL	B-Language
statement	O
in	O
the	O
Oracle	B-General_Concept
Database	I-General_Concept
executes	O
with	O
OCI	O
"	O
.	O
</s>
<s>
OCI	O
is	O
so	O
popular	O
that	O
,	O
in	O
addition	O
to	O
Oracle	B-Application
,	O
several	O
other	O
vendors	O
have	O
implemented	O
their	O
own	O
libraries	O
compatible	O
with	O
the	O
OCI	O
API	B-Application
.	O
</s>
<s>
Oracle	B-Application
's	O
enhanced	O
C++	B-Language
library	B-Library
,	O
Oracle	B-General_Concept
C++	I-General_Concept
Call	I-General_Concept
Interface	I-General_Concept
(	O
OCCI	O
)	O
,	O
which	O
provides	O
an	O
object-oriented	B-Language
interface	O
with	O
the	O
object-relational	B-General_Concept
features	O
of	O
the	O
Oracle	B-General_Concept
database	I-General_Concept
.	O
</s>
<s>
Due	O
to	O
the	O
complexity	O
of	O
the	O
OCI	O
API	B-Application
,	O
several	O
easier-to-use	O
OCI	O
wrapper	O
libraries	O
also	O
exist	O
,	O
such	O
as	O
:	O
</s>
<s>
the	O
open-source	O
libsqlora8	O
library	B-Library
(	O
deprecated	O
)	O
.	O
</s>
<s>
the	O
open-source	O
OCILIB	O
library	B-Library
.	O
</s>
<s>
the	O
Open	B-Operating_System
BSD	I-Operating_System
licensed	I-Operating_System
Oracle	B-Application
Template	O
Library	B-Library
OTL	O
library	B-Library
.	O
</s>
