How to select min and max values of a column in a datatable?

For the following datatable column, what is the fastest way to get the min and max values?

AccountLevel  
0  
1  
2  
3 

Easiar approach on datatable could be:

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

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

Use LINQ. It works just fine on datatables, as long as you convert the rows collection to an IEnumerable.

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

Edited to fix syntax; it's tricky when using LINQ on DataTables, and aggregating functions are fun, too.

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

This worked fine for me

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

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

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 :)

another way of doing this is

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

I am not sure on the performace part but this does give the correct output

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

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

Performance wise, this should be comparable. Use Select statement and Sort to get a list and then pick the first or last (depending on your sort order).

var col = dt.Select("AccountLevel", "AccountLevel ASC");

var min = col.First();
var max = col.Last();

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

I understand that the initial question was: What is the fastest way to get min and max values in a DataTable object, this may be one way of doing it:

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");

It's an easy way of achieving the same result without looping. But performance will need to be compared with previous answers. Thought I love Cylon Cats answer most.