?????????????丳???
????UPDATE dbo.EAVTable SET SomeData=LEFT(CAST(Value AS VARCHAR(1))??1)
????????????????PIVOIT????????????????????somedata?ж??з?NULL????????????????????????????????????????RecordID??SomeData?У????????????

????????????????????????????д?????T-SQL??????????????????????????????????????SQL Server??PIVOT???????????????????????????????????????塣???????????????????????????????е????????????????????????????????????????????????????????????????л?????з???????????????е????
-- Use a table expression to state explicitly which columns you want to
-- return from the base table. Therefore you can always control on which
-- columns the PIVOT operator is performing the grouping.
SELECT
RecordID??
FirstName??
LastName??
City??
Country
FROM
(
-- Table Expression
SELECT RecordID?? Element?? Value FROM EAVTable
) AS t
PIVOT(MAX(Value) FOR Element IN (FirstName?? LastName?? City?? Country)) AS t1
GO
?????????????????????????????????????PIVOT???????????????????????????????????С?????ζ??????????????????????PIVOT?????????
????С??
????????????????????????????SQL Server?????PIVOT?????????Σ??????????????????????Ч???????????????????????????????????????????????????????????????????PIVOT?????????????????????????????
??????PIVOT???????????????????????????????????????????????????