Fun with RAND()

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Fun with RAND()

Dave62

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November 4, 2014 at 9:51 pm

#312690

Comments posted to this topic are about the item Fun with RAND()

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Koen Verbeeck SSC Guru Points: 259165 More actions · Answer 1

Great question, thanks.

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RKaram SSCommitted Points: 1518 More actions · Answer 2

RKaram

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November 5, 2014 at 3:26 am

#1756689

Smart question :-):-)

thank you Dave

rabih

rkaram

palotaiarpad SSCertifiable Points: 5617 More actions · Answer 3

I hate myself not to read the relation correctly! 😀

SqlMel SSCrazy Points: 2901 More actions · Answer 4

Very good question. Thanks.

I almost got it wrong but I realized in time that the loop had a "<" and not "<="

---------------
Mel. 😎

Ed Wagner SSC Guru Points: 287026 More actions · Answer 5

SqlMel (11/5/2014)
Very good question. Thanks.
I almost got it wrong but I realized in time that the loop had a "<" and not "<="

That's what got me. Need more coffee.

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alvertorave Newbie Points: 9 More actions · Answer 6

I think the answer is wrong, you can only have 1 row, but you can execute the select 0 to 9 times returning a single row.

akljfhnlaflkj SSC Guru Points: 76202 More actions · Answer 7

akljfhnlaflkj

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November 5, 2014 at 6:32 am

#1756738

Nice question, thank you.

freeheel SSCrazy Points: 2404 More actions · Answer 8

alvertorave (11/5/2014)
I think the answer is wrong, you can only have 1 row, but you can execute the select 0 to 9 times returning a single row.

my thought exactly. i got it right, but ...

Brian.Klinect Mr or Mrs. 500 Points: 592 More actions · Answer 9

I forgot RAND() was exclusive. So we can get .99999..., which multiplies to 9.999999..... I take it then that storing a floating point number as an integer just truncates in SQL?

stephen.long.1 SSCrazy Points: 2591 More actions · Answer 10

Nice question, Dave, and a good explanation. Thanks!

Dana Medley SSCertifiable Points: 6764 More actions · Answer 11

Ed Wagner (11/5/2014)
SqlMel (11/5/2014)
Very good question. Thanks.
I almost got it wrong but I realized in time that the loop had a "<" and not "<="
That's what got me. Need more coffee.

Almost got me too. Thanks for the question.

Everything is awesome!

david.gugg SSCertifiable Points: 6141 More actions · Answer 12

Fun questions, thank you.

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Mike Hays SSCommitted Points: 1871 More actions · Answer 13

Interesting Question, I ran it a couple of time to see the different results...

Dave62 SSCertifiable Points: 7459 More actions · Answer 14

Brian.Klinect (11/5/2014)
I forgot RAND() was exclusive. So we can get .99999..., which multiplies to 9.999999..... I take it then that storing a floating point number as an integer just truncates in SQL?

This may be one of those "it depends" SQL Server answers.

Run this code and see if your results are the same as mine.

Declare @decFloat Float = 9.99999999999999;

Declare @intTest Integer = @decFloat;

Select @decFloat As [Float], @intTest As [Integer];

-- Returns: 9.999999999999999

Set @decFloat = 9.9999999999999999999999999;

Set @intTest = @decFloat;

Select @decFloat As [Float], @intTest As [Integer];

-- Returns: 109

Set @decFloat = 9.999999999999999;

Set @intTest = @decFloat;

Select @decFloat As [Float], @intTest As [Integer];

-- Returns: 1010It appears that sometimes we get rounding and sometimes truncating.

Enjoy!