checksum() of char, varchar, nchar, nvarchar, or sql_variant

Karam,
checksum and binary_checksum can be used for char, varchar, nchar, and
nvarchar. If you need it for sql_variant, you could convert the
sql_variant value to varbinary before applying the checksum or
binary_checksum. The following works fine for me (SQL Server 2000 sp3).
declare @.t table (
a char(10),
b nchar(10),
c varchar(10),
d nvarchar(10),
e sql_variant
)
insert into @.t values ('abc','def','ghi','jkl',cast(3.2 as sql_variant))
insert into @.t values ('abc','def','ghi','jkl',cast('mno' as sql_variant))
insert into @.t values ('abc','def','ghi','jkl',cast(PI() as sql_variant))
select
checksum(a),
checksum(b),
checksum(c),
checksum(d),
checksum(cast(e as varbinary(8000)))
from @.t
Steve Kass
Drew University
Karam Chand wrote:

>Hello,
>As the books online suggest we cannot generate checksum() value of the above types
using Checksum() or binary_checksum(), but my app requires it. Can somebody tell me
how to do that? Or is it just not possible... Maybe I can use some external program
min
g language?
>Karam
>Karam,
If you include a, b, c, d, and e in the output, it should look fine:
abc 34400 def 1132889051 ghi 40390
jkl -2087894091 3.2 135216
abc 34400 def 1132889051 ghi 40390
jkl -2087894091 mno 27535
abc 34400 def 1132889051 ghi 40390
jkl -2087894091 3.1415926535897931 200148684
You should be aware of the fact that CHECKSUM is not guaranteed to
return different values from different input. There are only
~4000000000 possible checksum values, but far more possible input values.
SK
Karam Chand wrote:

>Hello,
>I tried your query on SQL Server 2000 and checksum is always returning me t
he same value for different set of data. If you execute the checksum() for y
our above data, I am getting result:
>304227412 1174430821 25065 6974316 135216
>304227412 1174430821 25065 6974316 27535
>304227412 1174430821 25065 6974316 200148684
>As you can see, its all same so it is difficult to know the difference?
>Karam
> -- Steve Kass wrote: --
> Karam,
> checksum and binary_checksum can be used for char, varchar, nchar, a
nd
> nvarchar. If you need it for sql_variant, you could convert the
> sql_variant value to varbinary before applying the checksum or
> binary_checksum. The following works fine for me (SQL Server 2000 sp3
).
> declare @.t table (
> a char(10),
> b nchar(10),
> c varchar(10),
> d nvarchar(10),
> e sql_variant
> )
> insert into @.t values ('abc','def','ghi','jkl',cast(3.2 as sql_variant
))
> insert into @.t values ('abc','def','ghi','jkl',cast('mno' as sql_varia
nt))
> insert into @.t values ('abc','def','ghi','jkl',cast(PI() as sql_varian
t))
> select
> checksum(a),
> checksum(b),
> checksum(c),
> checksum(d),
> checksum(cast(e as varbinary(8000)))
> from @.t
> Steve Kass
> Drew University
> Karam Chand wrote:
>
gramming language?
>