Entity Get latest results based on date

Question

I have the following table:

------------------------------------
userid | testid | date     | result
1      | 1      | 18-01-01 | 1
1      | 1      | 18-01-09 | 6
1      | 3      | 18-01-09 | 5
1      | 3      | 18-01-10 | 2

Now i need to get 2 rows using Entity: The following:

------------------------------------
userid | testid | date     | result
1      | 1      | 18-01-09 | 6
1      | 3      | 18-01-10 | 2

I need a LINQ query that returns the latest result of each testid in the database. The userID/testID is the group. What is the best and fastest way to get this information?

Thanks,

Group by ? https://stackoverflow.com/questions/157786/how-do-i-get-the-max-row-with-a-group-by-in-linq-query? — Drag and Drop, Apr 16 '18 at 13:47
related. https://stackoverflow.com/questions/45939168/select-values-with-max-date-for-each-id?noredirect=1&lq=1 at least 5 exact dupe. — Drag and Drop, Apr 16 '18 at 13:48

score 2 · Answer 1 · answered Apr 16 '18 at 13:46

2

Just GroupBy() the testid and select the latest of each group

var result = ctx.Items.GroupBy(x => x.testid)
                      .Select(x => x.OrderByDescending(y => y.date).First());

answered Apr 16 '18 at 13:46

fubo

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Entity Get latest results based on date

1 Answers1