<s>
The	O
problem	O
of	O
database	B-General_Concept
repair	I-General_Concept
is	O
a	O
question	O
about	O
relational	B-Application
databases	I-Application
which	O
has	O
been	O
studied	O
in	O
database	B-General_Concept
theory	I-General_Concept
,	O
and	O
which	O
is	O
a	O
particular	O
kind	O
of	O
data	O
cleansing	O
.	O
</s>
<s>
The	O
problem	O
asks	O
about	O
how	O
we	O
can	O
"	O
repair	O
"	O
an	O
input	O
relational	B-Application
database	I-Application
in	O
order	O
to	O
make	O
it	O
satisfy	O
integrity	O
constraints	O
.	O
</s>
<s>
The	O
problem	O
of	O
database	B-General_Concept
repair	I-General_Concept
has	O
been	O
studied	O
to	O
understand	O
what	O
is	O
the	O
complexity	O
of	O
these	O
different	O
problem	O
variants	O
,	O
i.e.	O
,	O
can	O
we	O
efficiently	O
determine	O
information	O
about	O
the	O
state	O
of	O
the	O
repairs	O
,	O
without	O
explicitly	O
materializing	O
all	O
of	O
these	O
repairs	O
.	O
</s>
