<s>
A	O
data	B-Application
control	I-Application
language	I-Application
(	O
DCL	O
)	O
is	O
a	O
syntax	O
similar	O
to	O
a	O
computer	O
programming	O
language	O
used	O
to	O
control	O
access	O
to	O
data	O
stored	O
in	O
a	O
database	O
(	O
authorization	O
)	O
.	O
</s>
<s>
In	O
particular	O
,	O
it	O
is	O
a	O
component	O
of	O
Structured	B-Language
Query	I-Language
Language	I-Language
(	O
SQL	B-Language
)	O
.	O
</s>
<s>
Data	B-Application
Control	I-Application
Language	I-Application
is	O
one	O
of	O
the	O
logical	O
group	O
in	O
SQL	B-Language
Commands	O
.	O
</s>
<s>
SQL	B-Language
statements	O
are	O
used	O
to	O
perform	O
tasks	O
such	O
as	O
insert	B-Language
data	O
to	O
a	O
database	O
,	O
delete	B-Language
or	O
update	O
data	O
in	O
a	O
database	O
,	O
or	O
retrieve	O
data	O
from	O
a	O
database	O
.	O
</s>
<s>
Though	O
database	O
systems	O
use	O
SQL	B-Language
,	O
they	O
also	O
have	O
their	O
own	O
additional	O
proprietary	O
extensions	O
that	O
are	O
usually	O
only	O
used	O
on	O
their	O
system	O
.	O
</s>
<s>
For	O
Example	O
Microsoft	B-Application
SQL	I-Application
server	I-Application
uses	O
Transact-SQL	O
(	O
T-SQL	O
)	O
which	O
is	O
an	O
extension	O
of	O
SQL	B-Language
.	O
</s>
<s>
Similarly	O
Oracle	B-General_Concept
uses	O
PL-SQL	O
which	O
is	O
their	O
proprietary	O
extension	O
for	O
them	O
only	O
.	O
</s>
<s>
However	O
,	O
the	O
standard	O
SQL	B-Language
commands	O
such	O
as	O
"	O
Select	B-Language
"	O
,	O
"	O
Insert	B-Language
"	O
,	O
"	O
Update	O
"	O
,	O
"	O
Delete	B-Language
"	O
,	O
"	O
Create	O
"	O
,	O
and	O
"	O
Drop	O
"	O
can	O
be	O
used	O
to	O
accomplish	O
almost	O
everything	O
that	O
one	O
needs	O
to	O
do	O
with	O
a	O
database	O
.	O
</s>
<s>
The	O
operations	O
for	O
which	O
privileges	O
may	O
be	O
granted	O
to	O
or	O
revoked	O
from	O
a	O
user	O
or	O
role	O
apply	O
to	O
both	O
the	O
Data	B-Language
definition	I-Language
language	I-Language
(	O
DDL	O
)	O
and	O
the	O
Data	B-Language
manipulation	I-Language
language	I-Language
(	O
DML	O
)	O
,	O
and	O
may	O
include	O
CONNECT	O
,	O
SELECT	B-Language
,	O
INSERT	B-Language
,	O
UPDATE	O
,	O
DELETE	B-Language
,	O
EXECUTE	O
,	O
and	O
USAGE	O
.	O
</s>
<s>
As	O
per	O
Microsoft	B-Application
SQL	I-Application
Server	I-Application
there	O
are	O
four	O
groups	O
of	O
SQL	B-Language
Commands	O
.	O
</s>
<s>
For	O
example	O
:	O
GRANT	O
can	O
be	O
used	O
to	O
give	O
privileges	O
to	O
user	O
to	O
do	O
SELECT	B-Language
,	O
INSERT	B-Language
,	O
UPDATE	O
and	O
DELETE	B-Language
on	O
a	O
specific	O
table	O
or	O
multiple	O
tables	O
.	O
</s>
<s>
The	O
REVOKE	O
command	O
is	O
used	O
take	O
back	O
a	O
privilege	O
(	O
default	O
)	O
or	O
revoking	O
specific	O
command	O
like	O
UPDATE	O
or	O
DELETE	B-Language
based	O
on	O
requirements	O
.	O
</s>
<s>
GRANT	O
in	O
first	O
case	O
we	O
gave	O
privileges	O
to	O
user	O
User1	O
to	O
do	O
SELECT	B-Language
,	O
INSERT	B-Language
,	O
UPDATE	O
and	O
DELETE	B-Language
on	O
the	O
table	O
called	O
employees	O
.	O
</s>
<s>
REVOKE	O
with	O
this	O
command	O
we	O
can	O
take	O
back	O
privilege	O
to	O
default	O
one	O
,	O
in	O
this	O
case	O
,	O
we	O
take	O
back	O
command	O
INSERT	B-Language
on	O
the	O
table	O
employees	O
for	O
user	O
User1	O
.	O
</s>
<s>
Oracle	B-General_Concept
Database	I-General_Concept
divide	O
SQL	B-Language
commands	O
to	O
different	O
types	O
.	O
</s>
<s>
Data	B-Language
definition	I-Language
language	I-Language
(	O
DDL	O
)	O
statements	O
let	O
you	O
to	O
perform	O
these	O
tasks	O
:	O
</s>
<s>
So	O
Oracle	B-General_Concept
Database	I-General_Concept
DDL	O
commands	O
include	O
the	O
Grant	O
and	O
revoke	O
privileges	O
which	O
is	O
actually	O
part	O
of	O
Data	B-Application
control	I-Application
Language	I-Application
in	O
Microsoft	B-Application
SQL	I-Application
server	I-Application
.	O
</s>
<s>
Syntax	O
for	O
grant	O
and	O
revoke	O
in	O
Oracle	B-General_Concept
Database	I-General_Concept
:	O
</s>
<s>
In	O
PostgreSQL	B-Application
,	O
executing	O
DCL	O
is	O
transactional	B-General_Concept
,	O
and	O
can	O
be	O
rolled	O
back	O
.	O
</s>
<s>
SQLite	B-Language
does	O
not	O
have	O
any	O
DCL	O
commands	O
as	O
it	O
does	O
not	O
have	O
usernames	O
or	O
logins	O
.	O
</s>
<s>
Instead	O
,	O
SQLite	B-Language
depends	O
on	O
file-system	O
permissions	O
to	O
define	O
who	O
can	O
open	O
and	O
access	O
a	O
database	O
.	O
</s>
