可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试):
问题:
A table I have no control of the schema for, contains a column defined as varchar(50) which stores uniqueidentifiers in the format 'a89b1acd95016ae6b9c8aabb07da2010' (no hyphens)
I want to convert these to uniqueidentifiers in SQL for passing to a .Net Guid. However, the following query lines don't work for me:
select cast('a89b1acd95016ae6b9c8aabb07da2010' as uniqueidentifier) select convert(uniqueidentifier, 'a89b1acd95016ae6b9c8aabb07da2010')
and result in:
Msg 8169, Level 16, State 2, Line 1 Conversion failed when converting from a character string to uniqueidentifier.
The same queries using a hyphenated uniqueidentifier work fine but the data is not stored in that format.
Is there another (efficient) way to convert these strings to uniqueidentifiers in SQL. -- I don't want to do it in the .Net code.
回答1:
DECLARE @uuid VARCHAR(50) SET @uuid = 'a89b1acd95016ae6b9c8aabb07da2010' SELECT CAST( SUBSTRING(@uuid, 1, 8) + '-' + SUBSTRING(@uuid, 9, 4) + '-' + SUBSTRING(@uuid, 13, 4) + '-' + SUBSTRING(@uuid, 17, 4) + '-' + SUBSTRING(@uuid, 21, 12) AS UNIQUEIDENTIFIER)
回答2:
It would make for a handy function. Also, note I'm using STUFF instead of SUBSTRING.
create function str2uniq(@s varchar(50)) returns uniqueidentifier as begin -- just in case it came in with 0x prefix or dashes... set @s = replace(replace(@s,'0x',''),'-','') -- inject dashes in the right places set @s = stuff(stuff(stuff(stuff(@s,21,0,'-'),17,0,'-'),13,0,'-'),9,0,'-') return cast(@s as uniqueidentifier) end
回答3:
your varchar col C:
SELECT CONVERT(uniqueidentifier,LEFT(C, 8) + '-' +RIGHT(LEFT(C, 12), 4) + '-' +RIGHT(LEFT(C, 16), 4) + '-' +RIGHT(LEFT(C, 20), 4) + '-' +RIGHT(C, 12))
回答4:
SELECT CONVERT(uniqueidentifier,STUFF(STUFF(STUFF(STUFF('B33D42A3AC5A4D4C81DD72F3D5C49025',9,0,'-'),14,0,'-'),19,0,'-'),24,0,'-'))
回答5:
If your string contains special characters you can hash it to md5 and then convert it to a guid/uniqueidentifier.
回答6:
you are provided guid is not correct format(.net Provided guid).
begin try select convert(uniqueidentifier,'a89b1acd95016ae6b9c8aabb07da2010') end try begin catch print '1' end catch
