SQL?? ???? ? ??
?? ?
? ???? ? ?? ??? ?? ?? ??? ???? ?? SQL?? ?? ?? ???? ??? ?????.
??? ?? ? ???
??? ?? ??? ????.
- ??(?? ID, ??)
- ?? ???(?? ID, ??)
- ???(??? ID, ?? ID, ?? ID)
??
??? ? ?? ??? ?? ?? ??? ? ?? ?? ?? ??? ?? ??? ???? ????.
???
1. ??? ? ?? PIVOT? ?????.
??? ?? ?? ?? PIVOT ??? ??? ? ????.
select name, [Bronze], [Silver], [Gold], [Platinum], [AnotherOne]
from
(
select c.name,
cr.description,
r.typeid
from customers c
left join rewards r
on c.id = r.customerid
left join customerrewards cr
on r.typeid = cr.typeid
) x
pivot
(
count(typeid)
for description in ([Bronze], [Silver], [Gold], [Platinum], [AnotherOne])
) p;
2. ?? SQL? ??? PIVOT
? ??? ? ? ?? ?? ?? SQL? ?????.
DECLARE @cols AS NVARCHAR(MAX),
@query AS NVARCHAR(MAX)
select @cols = STUFF((SELECT ',' + QUOTENAME(description)
from customerrewards
group by description, typeid
order by typeid
FOR XML PATH(''), TYPE
).value('.', 'NVARCHAR(MAX)')
,1,1,'')
set @query = 'SELECT name,' + @cols + ' from
(
select c.name,
cr.description,
r.typeid
from customers c
left join rewards r
on c.id = r.customerid
left join customerrewards cr
on r.typeid = cr.typeid
) x
pivot
(
count(typeid)
for description in (' + @cols + ')
) p '
execute(@query)
?? ?
?? ?? ????? ROLLUP? ?????.
select name, sum([Bronze]) Bronze, sum([Silver]) Silver,
sum([Gold]) Gold, sum([Platinum]) Platinum, sum([AnotherOne]) AnotherOne
from
(
select name, [Bronze], [Silver], [Gold], [Platinum], [AnotherOne]
from
(
select c.name,
cr.description,
r.typeid
from customers c
left join rewards r
on c.id = r.customerid
left join customerrewards cr
on r.typeid = cr.typeid
) x
pivot
(
count(typeid)
for description in ([Bronze], [Silver], [Gold], [Platinum], [AnotherOne])
) p
) x
group by name with rollup
??
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? ??? ?? ??? ???? ?? SQL?? ?? ???? ???? ??? ??????? ?? ?????. ??? ??? PHP ??? ????? ?? ?? ??? ?????!
? AI ??
Undress AI Tool
??? ???? ??
Undresser.AI Undress
???? ?? ??? ??? ?? AI ?? ?
AI Clothes Remover
???? ?? ???? ??? AI ?????.
Clothoff.io
AI ? ???
Video Face Swap
??? ??? AI ?? ?? ??? ???? ?? ???? ??? ?? ????!
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??? ??, ???? ?? ????.
???? 13.0.1 ???
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