Split semicolon-delimited column into multiple columns - sql

Question

I'm trying to split a column, in SQL, into multiple columns.
My data looks like this:
Column1 | Column2 | Column3
ABC | 123 | User7;User9
nbm | qre | User1;User2;User3
POI | kjh | User1;User4;User5;User9
I need to split the Column3 into 4 new columns - each column containing the first "User". Each value within this column is separated by a semi-colon. One of the problems I have is that Column3 can have any number of users listed (all separated by semi-colons), so I don't know how many "new" columns I would need added.
The final output would need to look like:
Column1 | Column2 | Column3 | NewColumn1 | NewColumn2 | ETC.

Answer 1

Besides the fact that this is bad design here is a solution:
Just paste this into an empty query window and execute. Adapt to your needs...
declare #tbl TABLE(Column1 VARCHAR(15),Column2 VARCHAR(15),Column3 VARCHAR(150));
INSERT INTO #tbl VALUES
('ABC','123','User7;User9')
,('nbm','qre','User1;User2;User3')
,('POI','kjh','User1;User4;User5;User9');
WITH Splitted AS
(
SELECT Column1,Column2,CAST('<x>'+REPLACE(Column3,';','</x><x>')+'</x>' AS XML) AS Col3Splitted
FROM #tbl
)
SELECT Column1,Column2,Col3Splitted
,Col3Splitted.value('x[1]','varchar(max)') AS Column4
,Col3Splitted.value('x[2]','varchar(max)') AS Column5
,Col3Splitted.value('x[3]','varchar(max)') AS Column6
,Col3Splitted.value('x[4]','varchar(max)') AS Column7
/*Add as many as you need*/
FROM Splitted
Following the discussion with #SeanLang I add this dynamic approach. It will count the highest number of semicolons in Column3 and build the statement above dynamically.
CREATE TABLE #tbl (Column1 VARCHAR(15),Column2 VARCHAR(15),Column3 VARCHAR(150));
INSERT INTO #tbl VALUES
('ABC','123','User7;User9')
,('nbm','qre','User1;User2;User3')
,('POI','kjh','User1;User4;User5;User9');
DECLARE #sql VARCHAR(MAX)=
'WITH Splitted AS
(
SELECT Column1,Column2,CAST(''<x>''+REPLACE(Column3,'';'',''</x><x>'')+''</x>'' AS XML) AS Col3Splitted
FROM #tbl
)
SELECT Column1,Column2';
DECLARE #counter INT = 0;
WHILE #counter<=(SELECT MAX(LEN(Column3) - LEN(REPLACE(Column3, ';', ''))) from #tbl)
BEGIN
SET #counter=#counter+1;
SET #sql=#sql+',Col3Splitted.value(''x[' + CAST(#counter AS VARCHAR(10)) + ']'',''varchar(max)'') AS Column' + CAST(#counter+3 AS VARCHAR(10));
END
SET #sql=#sql+ ' FROM Splitted;';
EXEC (#sql);
DROP TABLE #tbl;

Answer 2

Here is a method that will be 100% dynamic. It will produce any number of columns based solely on the data it finds. The prevailing method for this around SO is a dynamic pivot. I prefer a dynamic crosstab as I find the syntax less obtuse and it has a slight benefit from a performance standpoint too. :)
Here is an article which explains this methodology very well. http://www.sqlservercentral.com/articles/Crosstab/65048/
Also, I am using the DelimitedSplit8K function originally penned by Jeff Moden and improved over time through the community. You can read about it and find the code for it here. http://www.sqlservercentral.com/articles/Tally+Table/72993/
if OBJECT_ID('tempdb..#Something') is not null
drop table #Something;
create table #something
(
Column1 varchar(5)
, Column2 varchar(5)
, Column3 varchar(50)
);
insert #something
select 'ABC', '123', 'User7;User9' union all
select 'nbm', 'qre', 'User1;User2;User3' union all
select 'POI', 'kjh', 'User1;User4;User5;User9';
declare #StaticPortion nvarchar(2000) = 'with orderedResults as
(
select s.Column1
, s.Column2
, x.Item
, x.ItemNumber
from #something s
cross apply dbo.DelimitedSplit8K(Column3, '';'') x
)
select Column1
, Column2
';
declare #DynamicPortion nvarchar(max) = '';
WITH
E1(N) AS (select 1 from (values (1),(1),(1),(1),(1),(1),(1),(1),(1),(1))dt(n)),
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
(
SELECT ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) FROM E4
)
select #DynamicPortion = #DynamicPortion + ', MAX(Case when ItemNumber = ' + CAST(N as varchar(6)) + ' then Item end) as Subject' + CAST(N as varchar(6)) + CHAR(10)
from cteTally t
where t.N <=
(
select top 1 COUNT(*)
from #something s
cross apply dbo.DelimitedSplit8K(Column3, ';') x
group by Column1
Order by COUNT(*) desc
);
declare #FinalStaticPortion nvarchar(2000) = ' from orderedResults group by Column1, Column2 order by Column1, Column2';
declare #SqlToExecute nvarchar(max) = #StaticPortion + #DynamicPortion + #FinalStaticPortion;
select #SqlToExecute;
--uncomment the following line when you are sure this is what you want to execute.
--exec sp_executesql #SqlToExecute;

Answer 3

For MySQl below code can be used. This is just a sample code
#num_Column3 := 1 + LENGTH(#Column3) - LENGTH(REPLACE(#Column3, '|', '')) AS num_Column3
,IF(#num_Column3 > 0, SUBSTRING_INDEX(SUBSTRING_INDEX(#Column3)), '|', 1), '|', -1), '') AS RC_user