Introduction - Repairing and Querying Databases under Aggregate Constraints - page 6

Year Section Subsection Type Value
t 1 2008 Receipts beginning cash drv 50
t 2 2008 Receipts cash sales det 900
t 3 2008 Receipts receivables det 100
t 4 2008 Receipts total cash receipts aggr 1250
t 5 2008 Disbursements payment of accounts det 1120
t 6 2008 Disbursements capital expenditure det 20
t 7 2008 Disbursements long-term financing det 80
t 8 2008 Disbursements total disbursements aggr 1220
t 9 2008 Balance net cash inflow drv 30
t 10 2008 Balance ending cash balance drv 80
t 11 2009 Receipts beginning cash drv 80
t 12 2009 Receipts cash sales det 1110
t 13 2009 Receipts receivables det 90
t 14 2009 Receipts total cash receipts aggr 1200
t 15 2009 Disbursements payment of accounts det 1130

t 16 2009 Disbursements capital expenditure det 40

t 17 2009 Disbursements long-term financing det 20

t 18 2009 Disbursements total disbursements aggr 1120

t 19 2 009 Balance net cash inflow drv 10

t 20 2009 Balance ending cash balance drv 90

Table 1.1 Relation BalanceSheets

phase. In fact, constraints κ , κ 2 and κ 3 are not satisfied on the acquired data shown

1

in Table 1.1 :

i) for year 2008, in section Receipts , the aggregate value of total cash receipts is
not equal to the sum of detail values of the same section: 900 1250;

ii) for year 2009, in section Disbursements , the aggregate value of total disburse-
ments is not equal to the sum of detail values of the same section: 1130

+ 100 =

+ 40 +

1120;
iii) for year 2009, the value of net cash inflow is not equal to the difference between
total cash receipts and total disbursements :10

20 =

= 1200 − 1120.

In the literature, two minimality criteria are generally employed for assessing
the reasonableness of a repair, namely the set - and card -minimality. Both these se-
mantics aim at giving an insight on the extent to which the repair preserves the
information represented in the original database. Specifically, a repair

ρ is said to

ρ such that ρ is a strict

be set -minimal [resp., card -minimal] if there is no repair

ρ contains fewer updates than

subset of ]. Initially, starting from the

seminal work [4], the research community has devoted its attention mainly to the

ρ [resp., ρ