How can I get a number from an nvarchar
I have a table called Foo and there is a column named Bar, which is an nvarchar
.
The values of Bar look like this: Prefix + Number
Examples:
Bar = 'abc123'
Bar = 'a1bc23'
I would like to select the Number part (second half) of Bar, which would be:
123 if Bar = 'abc123'
23 if Bar = 'a1bc23'
Presuming that the prefix doesn't end with a number how can I get t开发者_如何转开发he number part of Bar?
NOTES:
- We don't know the length of the prefix
- Either a T-SQL or a LINQ solution would be fine.
Thank you in advance for your time.
WITH T(C)
AS
(
SELECT 'a1bc23' UNION ALL
SELECT 'abc123' UNION ALL
SELECT 'FOO' UNION ALL
SELECT NULL UNION ALL
SELECT '456'
)
SELECT
CASE WHEN C LIKE '%[0-9]'
THEN CASE WHEN C LIKE '%[^0-9]%'
THEN RIGHT(C,PATINDEX('%[^0-9]%', REVERSE(C))-1)
ELSE C
END
END AS Number
FROM T
Returns
Number
------
23
123
NULL
NULL
456
Martin has a good answer for how to do it. While I'm sure this would work, it could turn out to be an expensive call, since you're doing a couple operations on a string field. If you have 1000s or millions of rows, this might not be performant.
I might suggest looking at the why you need to do this, and see if you can format your data in a way that would make it easier to handle this situation. Split the one field into 2 and have a prefix field and suffix field or something along those lines. Especially if these are "smart part numbers" or something along those lines, you would be able to do group by syntax easier.
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