How do I select a substring from two different patindex? - sql

Question

I have many different types of string, but they all follow the two same patterns:
ABC123-S-XYZ789
ABC123-P-XYZ789
QUESTION 1:
I know how I can extract the first part: ABC123
But how do I extract the second part??? XYZ789
QUESTION 2:
I can't tell beforehand if the string follows the -S- pattern or the -P- pattern, it can be different each time. Anyone who know how I can solve this?
Thanks! / Sophie

Answer 1

You can try following code:
SELECT CASE WHEN #a LIKE '%-S-%' THEN right(#a, CHARINDEX('-S-', #a)-1)
WHEN #a LIKE '%-P-%' THEN right(#a, CHARINDEX('-P-', #a)-1)
ELSE NULL END AS 'ColName'
FROM tablename

Answer 2

Is this what you need?
DECLARE #Input VARCHAR(100) = 'ABC123-S-XYZ789'
SELECT
FirstPart = SUBSTRING(
#Input,
1,
CHARINDEX('-', #Input) - 1),
SecondPart = SUBSTRING(
#Input,
LEN(#Input) - CHARINDEX('-', REVERSE(#Input)) + 2,
100),
Pattern = CASE
WHEN #Input LIKE '%-S-%' THEN 'S'
WHEN #Input LIKE '%-P-%' THEN 'P' END

Answer 3

You can use parsename() if the string has always this kind of parts such as ABC123-S-XYZ789
select col, parsename(replace(col, '-', '.'), 1)
However, the parsename() requires the SQL Server+12 if not then you can use reverse()
select col, reverse(left(reverse(col), charindex('-', reverse(col))-1))

Answer 4

If you're using SQL Server 2016 or newer, you can use STRING_SPLIT
CREATE TABLE #temp (string VARCHAR(100));
INSERT #temp VALUES ('ABC123-S-XYZ789'),('ABC123-P-XYZ789');
SELECT *, ROW_NUMBER() OVER (PARTITION BY string ORDER BY string)
FROM #temp t
CROSS APPLY STRING_SPLIT(t.string, '-');
I can't tell beforehand if the string folllows the -S- pattern or the -P- pattern
You can then use a CTE to get a specific part of the string:
WITH cte AS (
SELECT *, ROW_NUMBER() OVER (PARTITION BY string ORDER BY string) rn
FROM #temp t
CROSS APPLY STRING_SPLIT(t.string, '-')
)
SELECT * FROM cte WHERE rn = 2