How to select minimum and maximum column values ​​in datatable?

Question

For the next data column, what is the fastest way to get the min and max values?

AccountLevel 0 1 2 3 

Answer 1

 int minAccountLevel = int.MaxValue; int maxAccountLevel = int.MinValue; foreach (DataRow dr in table.Rows) { int accountLevel = dr.Field<int>("AccountLevel"); minAccountLevel = Math.Min(minAccountLevel, accountLevel); maxAccountLevel = Math.Max(maxAccountLevel, accountLevel); } 

Yes, this is really the fastest way. Using the Linq Min and Max extensions will always be slower because you need to iterate twice. You could use Linq Aggregate , but the syntax won't be much prettier than it already is.

Answer 2

An easy datatable approach might be:

 int minLavel = Convert.ToInt32(dt.Compute("min([AccountLevel])", string.Empty)); 

Answer 3

Use LINQ. It works fine on datatables if you convert a collection of strings to IEnumerable.

 List<int> levels = AccountTable.AsEnumerable().Select(al => al.Field<int>("AccountLevel")).Distinct().ToList(); int min = levels.Min(); int max = levels.Max(); 

Edited to correct syntax; this is difficult when using LINQ in DataTables, as well as aggregation functions too.

Yes, this can be done with a single query, but you will need to generate a list of results, and then use .Min () and .Max () as aggregating functions in separate statements.

Answer 4

The most efficient way to do this (believe it or not) is to make two variables and write a for loop.

Answer 5

 var answer = accountTable.Aggregate(new { Min = int.MinValue, Max = int.MaxValue }, (a, b) => new { Min = Math.Min(a.Min, b.Field<int>("AccountLevel")), Max = Math.Max(a.Max, b.Field<int>("AccountLevel")) }); int min = answer.Min; int max = answer.Max; 

1 iteration, linq style :)

Answer 6

It worked great for me

 int max = Convert.ToInt32(datatable_name.AsEnumerable() .Max(row => row["column_Name"])); 

Answer 7

Another way to do this:

 int minLavel = Convert.ToInt32(dt.Select("AccountLevel=min(AccountLevel)")[0][0]); 

I'm not sure about the execution part, but it gives the right conclusion

Answer 8

 var min = dt.AsEnumerable().Min(row => row["AccountLevel"]); var max = dt.AsEnumerable().Max(row => row["AccountLevel"]); 

Answer 9

Efficiency, it should be comparable. Use the Select and Sort operator to get a list, and then select the first or last (depending on your sort order).

 var col = dt.Select("AccountLevel", "AccountLevel ASC"); var min = col.First(); var max = col.Last(); 

Answer 10

 Session["MinDate"] = dtRecord.Compute("Min(AccountLevel)", string.Empty); Session["MaxDate"] = dtRecord.Compute("Max(AccountLevel)", string.Empty); 

Answer 11

I don't know how my solution compares performance with previous answers.

I understand that the initial question is: what is the fastest way to get the min and max values ​​in a DataTable, this may be one way to do this:

 DataView view = table.DefaultView; view.Sort = "AccountLevel"; DataTable sortedTable = view.ToTable(); int min = sortedTable.Rows[0].Field<int>("AccountLevel"); int max = sortedTable.Rows[sortedTable.Rows.Count-1].Field<int>("AccountLevel"); 

This is an easy way to achieve the same result without a loop. But performance should be comparable to previous answers. I think I love Cylon Cats to answer most.