<s>
SQL/DS	B-Application
(	O
Structured	O
Query	O
Language/Data	O
System	O
)	O
,	O
released	O
in	O
1981	O
,	O
was	O
IBM	O
's	O
first	O
commercial	O
relational-database	O
management	O
system	O
.	O
</s>
<s>
SQL/DS	B-Application
ran	O
on	O
the	O
DOS/VSE	B-Application
and	O
VM/CMS	B-Application
operating	O
systems	O
.	O
</s>
<s>
A	O
little	O
later	O
,	O
IBM	O
also	O
introduced	O
Db2	B-Application
,	O
another	O
SQL-based	O
DBMS	O
,	O
this	O
one	O
for	O
the	O
MVS	B-Application
operating	I-Application
system	I-Application
.	O
</s>
<s>
The	O
two	O
products	O
have	O
coexisted	O
since	O
then	O
;	O
however	O
,	O
SQL/DS	B-Application
was	O
rebranded	O
as	O
"	O
DB2	B-Application
for	O
VM	B-Application
and	O
VSE	B-Application
"	O
in	O
the	O
late	O
1990s	O
.	O
</s>
<s>
Software	O
AG	O
's	O
Natural	O
4GL	B-Language
was	O
an	O
early	O
third-party	B-Application
software	I-Application
product	I-Application
that	O
facilitated	O
using	O
SQL/DS	B-Application
.	O
</s>
<s>
Software	O
AG	O
used	O
the	O
name	O
Natural	O
2/SQL	O
-DS	O
and	O
,	O
later	O
on	O
,	O
for	O
a	O
related	O
offering	O
,	O
Natural	O
2/DB2	O
.	O
</s>
