Get All data from one table according to another, using Temporal Tables
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SELECT ss.validfrom AS 'status validFrom', ss.ID, ss.PrimaryStatusID, ca.[students validFrom], ca.ID, ca.IsFoster 
FROM StatusForStudents ss
CROSS APPLY
(SELECT TOP(1) s.validfrom AS 'students validFrom', s.ID,s.IsFoster
FROM Students s 
WHERE s.validfrom&lt;=ss.validfrom
ORDER BY s.validfrom DESC
) AS ca