SQL Server 2017

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create table t1 (a int, b int, c int)
insert into t1 values
(1, NULL, 100),
(2, NULL, NULL),
(3, 1, 2)
3 rows affected

SELECT *, BINARY_CHECKSUM(a,b) AS bc
FROM t1


a
b
c
bc


1
null
100
2147483631

2
null
null
2147483615

3
1
2
49


create table t2 (a int, b int, c int)
insert into t2 values
(1, NULL, 100),
(2, NULL, NULL)
2 rows affected

SELECT *, BINARY_CHECKSUM(a,b) AS bc
FROM t2


a
b
c
bc


1
null
100
2147483631

2
null
null
2147483615


SELECT *, BINARY_CHECKSUM(a,b) AS bc
FROM (VALUES(1, 1, 100),
            (2, 3, 4),(3,1,1)) s(id,a,b);


id
a
b
bc


1
1
100
116

2
3
4
52

3
1
1
17


SELECT *, BINARY_CHECKSUM(a,b) AS bc
FROM (VALUES(1, 1, 100),
            (2, 3, 4)) s(id,a,b);


id
a
b
bc


1
1
100
116

2
3
4
52

a	b	c	bc
1	null	100	2147483631
2	null	null	2147483615
3	1	2	49

a	b	c	bc
1	null	100	2147483631
2	null	null	2147483615