SQL Server 2012 Removing part of string before and after specific, repeating character - sql

Question

Would you please assist with a perplexing string operator problem?
I need to parse a NVARCHAR(32), not null column called MachineName from table dbo.Log. The format is either:
AA-BBB-CCC-DDD
AA-BBB-CCCC-DDD
AA-BBB-CCC-DDDD
AA-BBB-CCCC-DDDD
I need the Result Set (as [Code]) to be either CCC or CCCC.
I consulted this article:
http://basitaalishan.com/2014/02/23/removing-part-of-string-before-and-after-specific-character-using-transact-sql-string-functions/
With this code:
SELECT DISTINCT [MachineName]
,REPLACE(SUBSTRING([MachineName], CHARINDEX('-', [MachineName],6), LEN([MachineName])), '-', '') AS [Code]
FROM [dbo].[Log]
My current Result Set is fine on the left, but the right needs refinement.
CCCDDD
CCCCDDDD
I would defintely appreciate your help! Thank you in advance

Answer 1

You can improvise on this: http://sqlfiddle.com/#!3/9eecb7d/588
with test as (
select cast('AA-BBB-CCC-DDD' as nvarchar(32)) as field1
union all
select cast('AA-BBB-CCCC-DDD' as nvarchar(32)) as field1
union all
select cast('AA-BBB-CCC-DDDD' as nvarchar(32)) as field1
union all
select cast('AA-BBB-CCCC-DDDD' as nvarchar(32)) as field1
)
select
substring(
substring(field1,8,32),
1,
charindex('-', substring(field1,8,32))-1
)
from test
Result:
CCC
CCCC
CCC
CCCC
With substring, we ignore the first 7 characters and start with 8th character. That'll give us CCCC-DDD and such. charindex will tell us the position of - in CCCC-DDD and such. We reapply substring on the substring; starting with first position and capturing all up until - was found.
In your case, you could do:
select distinct
substring(
substring(MachineName,8,32),
1,
charindex('-', substring(MachineName,8,32))-1
) as Code
from dbo.Log