Inexplicable Behaviour of Select

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Inexplicable Behaviour of Select

Author

Topic

PoojaJ
Starting Member

10 Posts

Posted - 2007-04-13 : 02:27:38

Hi

Just tried to Run the Following statement in Query Analyzer
Select convert(varchar(9),convert(integer,1234567890))

The Output was an * (asterisk)
Can Some one Explain Y??

Thanks in advance

SwePeso
Patron Saint of Lost Yaks

30421 Posts

Posted - 2007-04-13 : 02:34:58

You expected that only the first 9 digits would be converted, right?
NO! The answer is readable in Books Online.

First I opened Books Online and typed CONVERT in the search box. Then I scrolled down to see what information there is.

quote:

Truncating and Rounding Results

When you convert character or binary expressions (char, nchar, nvarchar, varchar, binary, or varbinary) to an expression of a different data type, data can be truncated, only partially displayed, or an error is returned because the result is too short to display. Conversions to char, varchar, nchar, nvarchar, binary, and varbinary are truncated, except for the conversions shown in the following table.

From data type                                       To data type  Result  
---------------------------------------------------  ------------  ------
int, smallint, or tinyint                            char          *
                                                     varchar       *
                                                     nchar         E
                                                     nvarchar      E

money, smallmoney, numeric, decimal, float, or real  char          E
                                                     varchar       E
                                                     nchar         E
                                                     nvarchar      E

Peter Larsson
Helsingborg, Sweden

madhivanan
Premature Yak Congratulator

22864 Posts

Posted - 2007-04-13 : 03:27:19

I expect Error rather than *

Madhivanan

Failing to plan is Planning to fail

PoojaJ
Starting Member

10 Posts

Posted - 2007-04-13 : 03:34:00

Thanks a lot for ur Reply

khtan
In (Som, Ni, Yak)

17689 Posts

Posted - 2007-04-13 : 03:34:44

quote:
Originally posted by madhivanan

I expect Error rather than *

Madhivanan

Failing to plan is Planning to fail

This behavior is by design

madhivanan
Premature Yak Congratulator

22864 Posts

Posted - 2007-04-13 : 03:41:38

May be bad design

Madhivanan

Failing to plan is Planning to fail

harsh_athalye
Master Smack Fu Yak Hacker

5581 Posts

Posted - 2007-04-13 : 04:29:07

May be asterisk is chosen because it is commonly used wild-card character which used to represent one or more characters or may be because it resembles shape of bug

Harsh Athalye
India.
"The IMPOSSIBLE is often UNTRIED"

khtan
In (Som, Ni, Yak)

17689 Posts

Posted - 2007-04-13 : 04:35:02

quote:
because it resembles shape of bug

This sounds like a more likely reason

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