By using db<>fiddle, you agree to license everything you submit by Creative Commons CC0.
CREATE FUNCTION [dbo].[DelimitedSplit8K]
--===== Define I/O parameters
(@pString VARCHAR(8000), @pDelimiter VARCHAR(16))
--WARNING!!! DO NOT USE MAX DATA-TYPES HERE! IT WILL KILL PERFORMANCE!
RETURNS TABLE WITH SCHEMABINDING AS
RETURN
--===== "Inline" CTE Driven "Tally Table" produces values from 1 up to 10,000...
-- enough to cover VARCHAR(8000)
WITH E1(N) AS (
SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL
SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL
SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1
), --10E+1 or 10 rows
E2(N) AS (SELECT 1 FROM E1 a, E1 b), --10E+2 or 100 rows
E4(N) AS (SELECT 1 FROM E2 a, E2 b), --10E+4 or 10,000 rows max
cteTally(N) AS (--==== This provides the "base" CTE and limits the number of rows right up front
-- for both a performance gain and prevention of accidental "overruns"
SELECT TOP (ISNULL(DATALENGTH(@pString),0)) ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) FROM E4
),
cteStart(N1) AS (--==== This returns N+1 (starting position of each "element" just once for each delimiter)
SELECT 1 UNION ALL
SELECT t.N+ Len( @pDelimiter ) FROM cteTally t WHERE SUBSTRING(@pString,t.N, Len( @pDelimiter ) ) = @pDelimiter
),
cteLen(N1,L1) AS(--==== Return start and length (for use in substring)
SELECT s.N1,
ISNULL(NULLIF(CHARINDEX(@pDelimiter,@pString,s.N1),0)-s.N1 ,8000)
FROM cteStart s
)
--===== Do the actual split. The ISNULL/NULLIF combo handles the length for the final element when no delimiter is found.
SELECT ItemNumber = ROW_NUMBER() OVER(ORDER BY l.N1),
Item = SUBSTRING(@pString, l.N1, l.L1)
FROM cteLen l;
declare @QandA as NVarChar(1000) = '<b>Q1:</b><br />A1<br /><br /><b>Q2:</b><br />A2<br /><br /><b>Q3:</b><br />A3<br /><br /><b>Q4:</b><br />A4<br /><br />';
-- A single split gets Q/A pairs:
select ItemNumber, Item
from dbo.DelimitedSplit8K( @QandA, '<br /><br />' )
order by ItemNumber;
-- A second split gets Q's and A's:
with QAPairs as (
select ItemNumber as QuestionNumber, Item as QA
from dbo.DelimitedSplit8K( @QandA, '<br /><br />' ) )
select QuestionNumber, QA, ItemNumber, Item, case when ItemNumber % 2 = 1 then 'Q' else 'A' end as 'Q/A'
from QAPairs cross apply
dbo.DelimitedSplit8K( QA, '<br />' );
ItemNumber | Item |
---|---|
1 | <b>Q1:</b><br />A1 |
2 | <b>Q2:</b><br />A2 |
3 | <b>Q3:</b><br />A3 |
4 | <b>Q4:</b><br />A4 |
5 |
QuestionNumber | QA | ItemNumber | Item | Q/A |
---|---|---|---|---|
1 | <b>Q1:</b><br />A1 | 1 | <b>Q1:</b> | Q |
1 | <b>Q1:</b><br />A1 | 2 | A1 | A |
2 | <b>Q2:</b><br />A2 | 1 | <b>Q2:</b> | Q |
2 | <b>Q2:</b><br />A2 | 2 | A2 | A |
3 | <b>Q3:</b><br />A3 | 1 | <b>Q3:</b> | Q |
3 | <b>Q3:</b><br />A3 | 2 | A3 | A |
4 | <b>Q4:</b><br />A4 | 1 | <b>Q4:</b> | Q |
4 | <b>Q4:</b><br />A4 | 2 | A4 | A |
5 | 1 | Q |