Usando solo expresiones de tabla comunes, también podemos obtener los resultados requeridos, como se muestra a continuación:-
Primero configuremos los datos
declare @original table(
[value] varchar(250),
[unit] varchar(250)
)
insert into @original values
('4 ; 5','mg ; kg '),
('50','mg ' ),
('7.5 ; 325','kg ; mg ' ),
('100 ; 1.5 ; 50 ','mg ; g ; mg' )
Ahora, construyamos las expresiones de tabla comunes:-
;with cte as (
select o.[value]+';' [value],o.[unit]+';' [unit],row_number() over (ORDER BY (Select 0)) [row] from @original o
),cte2 as (
select *
,1 [ValueStart],CHARINDEX(';',[value]) [ValueEnd]
,1 [UnitStart],CHARINDEX(';',[unit]) [UnitEnd]
from cte
),cte3 as (
select * from cte2
union all
select [value],[unit],[row]
,[ValueEnd]+1 [ValueStart],CHARINDEX(';',[value],[ValueEnd]+1) [ValueEnd]
,[UnitEnd]+1 [UnitStart],CHARINDEX(';',[unit],[UnitEnd]+1) [UnitEnd]
from cte3 where [UnitEnd]>0
),cte4 as (
select *,row_number() over (partition by [row] order by [row]) [subRow]
, rtrim(ltrim(substring([unit],[UnitStart],[UnitEnd]-[UnitStart]))) [subUnit]
, rtrim(ltrim(substring([value],[ValueStart],[ValueEnd]-[ValueStart]))) [subValue]
from cte3
where [UnitEnd]>0
),cte5 as (
select subRow,[row],[subValue],[subUnit],cast([subValue]+' '+[subUnit] as varchar(max)) [ValueUnit] from cte4 where subRow=1
union all
select cte4.subRow,cte4.[row],cte4.[subUnit],cte4.[subValue]
,cte5.[ValueUnit]+';'+ cte4.[subValue]+' '+cte4.[subUnit] [ValueUnit]
from cte4
inner join cte5 on (cte5.subRow+1)=cte4.subRow and cte5.[row]=cte4.[row]
),cte6 as (
select *,row_number() over (partition by [row] order by subRow desc) [selected] from cte5
)
select ValueUnit from cte6
where [selected]=1
order by [row]
Los resultados serán los siguientes:-
ValueUnit
============
4 mg;5 kg
50 mg
7.5 kg;325 mg
100 mg;1.5 g;50 mg
