CODEWITHSUNDEEP
c#sqllinqlambda
tsohtan
tsohtan

Reputation: 850

Lambda Expression Select Min and Max at the same time

How do I convert this code to a Lambda expression when there are two columns to select at the same time?

LINQ

var lq=(from a in tbl
          group a by 0 into b
          select new { intYear = b.Min(p => p.intYear), tintMonth = b.Max(p => p.tintMonth) }
    ).SingleOrDefault();

T-SQL

SELECT MIN(intYear), MAX(tintMonth)
FROM tbl

Lambda Expression

tbl.Select(x => x.intYear).Min();  //Can't figure how to select if 2 columns

Upvotes: 4

Views: 9454

Answers (1)

lc.
lc.

Reputation: 116498

If you're intent on returning a "row" rather than two values, you can group all the rows together as you do in the first LINQ expression:

tbl.GroupBy(t => 1)
   .Select(g => new { intYear = g.Min(p => p.intYear), tintMonth = g.Max(p => p.tintMonth) })

Note, I assume this is for LINQ-to-SQL. For plain old objects, this would most likely result in three iterations through the collection. One to do the grouping, one for the Min(), and one for Max(). For large collections, you would be be better off looping once and doing it the good-ol'-fashioned way with a single foreach over the collection.

Upvotes: 6

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