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Get count of occurrence of certain value in DataTable column

I am creating a DataTable dynamically, NOT from SQL. I need to count the number of times the value of '0' appears in the 'testresult' column. So far everything I've tried returns a count of 0, even though the table has 1 entry of '0' in the testresult column. HELP! :)
I've tried:
1)
DataRow[] rows = dtMerged.Select("testresult Like '%0%'");
int rowcount = rows.Length;
int rowcount = dtMerged.Select("testresult = 0").Count();
int rowcount = Convert.ToInt32(dtMerged.Compute("Count(testresult)", "testresult Like '%0%'"));
var rowcount = dtMerged.AsEnumerable()
.GroupBy(r => r.Field<string>("testresult"))
.Select(r => new
{
Str = r.Key,
Count = r.Count()
});
All of these options give me a rowcount of '0' except number 4, which resulted in a value of 'null'. Here is an image of the DataTable in question.
Thanks!
Here is a sample of code that will create essentially the same DataTable that I'm working with, my creation method is a bit complicated for copy/pasting:
DataTable dtMerged= new DataTable();
dtMerged.Columns.Add("ID", typeof(int));
dtMerged.Columns.Add("hbserial", typeof(string));
dtMerged.Columns.Add("testresult", typeof(string));
dtMerged.Rows.Add(0, "testhashboard1", "1");
dtMerged.Rows.Add(1, "samplehashboard1", "1");
dtMerged.Rows.Add(2, "samplehashboard2", "0");
return dtMerged;
//Attempt 1
DataRow[] rows = dtMerged.Select("testresult Like '%0%'");
int rowcount = rows.Length;
//Attempt 2
int rowcount = dtMerged.Select("testresult = 0").Count();
//Attempt 3
int rowcount = Convert.ToInt32(dtMerged.Compute("Count(testresult)", "testresult Like '%0%'"));
//Attempt 4
var rowcount = dtMerged.AsEnumerable()
.GroupBy(r => r.Field<string>("testresult"))
.Select(r => new
{
Str = r.Key,
Count = r.Count()
});

Group and Sum DataTable

I have Data Table with the following data
Number Type Order count
1 1 R 1
1 1 R 1
1 1 R 1
1 2 R 1
I am looking to get to this result
Number Type Order count
1 1 R 3
1 2 R 1
How can I group by three columns
var result = dt.AsEnumerable()
.GroupBy(x => {x.Field<string>("Number"))//need to group by Type and order also need to sum te total counts

rgoal
Your question made me curious, so I did some digging on Stack Overflow.
esc's answer appears will also solve your issue. It is posted under: How do I use SELECT GROUP BY in DataTable.Select(Expression)?:
Applying his method to your problem gave me this solution:
DataTable dt2 = dt.AsEnumerable()
.GroupBy(r => new { Number = r["Number"], Type = r["Type"], Order = r["Order"] })
.Select(g =>
{
var row = dt.NewRow();
row["Number"] = g.Key.Number;
row["Type"] = g.Key.Type;
row["Order"] = g.Key.Order;
row["Count"] = g.Count();
return row;
}).CopyToDataTable();
This will return a DataTable matching the schema of the input DataTable with the grouping and counts you requested.
Here is the full code I use to verify in LINQPad:
DataTable dt = new DataTable("Demo");
dt.Columns.AddRange
(
new DataColumn[]
{
new DataColumn ( "Number", typeof ( int ) ),
new DataColumn ( "Type", typeof ( int ) ),
new DataColumn ( "Order", typeof ( string ) ),
new DataColumn ( "Count", typeof ( int ) )
}
);
dt.Rows.Add(new object[] { 1,1,"R", 1 });
dt.Rows.Add(new object[] { 1,1,"R", 1 });
dt.Rows.Add(new object[] { 1,1,"R", 1 });
dt.Rows.Add(new object[] { 1,2,"R", 1 });
DataTable dt2 = dt.AsEnumerable()
.GroupBy(r => new { Number = r["Number"], Type = r["Type"], Order = r["Order"] })
.Select(g =>
{
var row = dt.NewRow();
row["Number"] = g.Key.Number;
row["Type"] = g.Key.Type;
row["Order"] = g.Key.Order;
row["Count"] = g.Count();
return row;
}).CopyToDataTable();
foreach (DataRow row in dt2.Rows)
{
for (int i = 0; i < dt2.Columns.Count; i++)
Console.Write("{0}{1}",
row[i], // Print column data
(i < dt2.Columns.Count - 1)? " " : Environment.NewLine); // Print column or row separator
}
Here are the results:
1 1 R 3
1 2 R 1

Sort datatable based on value in the column

I have a datatable,
PId PName Qty
123 XYZ 2
223 ABC 4
434 PQR 33
I want to sort it on "PName" but not asc/ desc order,
If I pass PName as "PQR", then PQR should come first and then rest of the rows,
same if I pass "ABC" then "ABC" should come first and then rest of the rows.
Basically wants to reshuffle the rows where first row should be the "PName" which I am holding in a variable.
Thanks
Desired output
If I have "ABC", then the above datatable should reshuffle as,
PId PName Qty
223 ABC 4
123 XYZ 2
434 PQR 33
If I have "PQR", then the above datatable should reshuffle as,
PId PName Qty
434 PQR 33
123 XYZ 2
223 ABC 4

DataTable dt = new DataTable();
dt.Columns.Add("PId", typeof(Int32));
dt.Columns.Add("PName", typeof(string));
dt.Columns.Add("Qty", typeof(Int32));
dt.Rows.Add(123, "XYZ", 2);
dt.Rows.Add(223, "ABC", 4);
dt.Rows.Add(434, "PQR", 33);
var stkLists = dt.AsEnumerable().ToList();
var matchList = stkLists.Where(m => m["PName"].ToString().StartsWith("PQR")).ToList();
var FinalList = matchList.Concat(stkLists.Except(matchList).ToList());

Try like this:
DataTable dt = new DataTable();
dt.Columns.Add("PId", typeof(Int32));
dt.Columns.Add("PName", typeof(string));
dt.Columns.Add("Qty", typeof(Int32));
dt.Rows.Add(123, "XYZ", 2);
dt.Rows.Add(223, "ABC", 4);
dt.Rows.Add(434, "PQR", 33);
string Name = "PQR";
DataTable newDt = dt.Rows.Cast<DataRow>().Where(r => r.ItemArray[1] == Name).CopyToDataTable();
dt = dt.Rows.Cast<DataRow>().Where(r => r.ItemArray[1] != Name).CopyToDataTable();
newDt.Merge(dt);

slice a datatable for daterange , sum up counts and create a custom table?

Is there any easy way to slice a datatable for a range and sum up counts for a range?
let say I have below datatable
Date Count
5/9/2016 5
5/10/2016 1
5/11/2016 2
5/12/2016 4
5/13/2016 3
5/14/2016 2
5/15/2016 1
5/16/2016 4
If I slice it by 2 then it will club 2 rows ..something like
DateRange Count
5/9/2016-5/10/2016 6
5/11/2016-5/12/2016 6
5/13/2016-5/14/2016 5
5/15/2016-5/16/2016 5
If I slice it by 3 then it will club 3 rows ..something like
DateRange Count
5/9/2016-5/11/2016 8
5/12/2016-5/14/2016 9
5/15/2016-5/16/2016 5
I am trying to show my data in a asp:Chart (StackedColumn) chart for a date range. date range varies between 7,15,30,60,90,150,365 days ..almost each day there are some data entries and there are a custom date control to select date also . let say a user select a date range for 200 days , for 200 days their will 200 records . now is there any way to club up the data and show in that chart .Currently I am trying to do it by month but as I know there are a custom date range so I need to come up with a different workaround , any help on it .
public DataTable GetTable()
{
// Here we create a DataTable with four columns.
DataTable table = new DataTable();
table.Columns.Add("Date", typeof(DateTime));
table.Columns.Add("R", typeof(int));
table.Columns.Add("C", typeof(int));
// Here we add five DataRows.
for (int i = 0; i <= dayschunk; i++)
{
table.Rows.Add(DateTime.Now.Date.AddDays(-i).ToString("MMM-dd"), new Random().Next(0, 99), new Random().Next(0, 99));
}
var results = from row in table.AsEnumerable()
group row by new { Date = row.Field<DateTime>("Date").Month } into rowgroup
select new
{
rowgroup.Key.Date,
Remidiated = rowgroup.Sum(r => r.Field<int>("R")),
Stucked = rowgroup.Sum(r => r.Field<int>("C"))
};
DataTable filtered = new DataTable();
filtered.Columns.Add("DateRange", typeof(int));
filtered.Columns.Add("R", typeof(int));
filtered.Columns.Add("C", typeof(int));
foreach (var item in results)
{
table.Rows.Add(CultureInfo.CurrentCulture.DateTimeFormat.GetMonthName(item.Date), item.Remidiated, item.Stucked);
}
//table.Rows.Add(2,new DateTime(2016, 05, 02), 50, 50);
//table.Rows.Add(2,new DateTime(2016, 05, 07), 3, 4);
//table.Rows.Add(2,new DateTime(2016, 05, 05), 16, 10);
return filtered;
}

You could do this using Select overload to pass an index and creating chunks with the given size.
DataTable result = new DataTable();
result.Columns.Add("DateRange", typeof(string));
result.Columns.Add("Count", typeof(int));
int chunk = 2;
result = table.AsEnumerable()
.Select((row,i) => new {gid= i/chunk, row})
.GroupBy(x=>x.gid)
.Select(x=>
{
var row= result.NewRow();
row["DateRange"] = string.Format("{0}-{1}", x.First().row.Field<DateTime>("Date"), x.Last().row.Field<DateTime>("Date"));
row["Count"]= x.Sum(r=>r.row.Field<int>("R"));
return row;
}).CopyToDataTable<DataRow>();
Check this Example
Note: I have not applied output formatting, but you could this easily and I will leave it to you.

How to Compare Two dataTable and Update non matched rows in a DataTable which gives the resultDataTable?

MasterData
Id Name
1 CENTRAL
2 EAST
3 EAST CENTRAL
4 EAST COASTAL
5 NORTH
6 NORTH WEST
7 SOUTH
8 SOUTH CENTRAL
9 WEST
Data Received
Id Name Value
1 CENTRAL 125.65
5 NORTH 553.21
i want the Result to be as followes
Id Name Value
1 CENTRAL 125.65
2 EAST 0.0
3 EAST CENTRAL 0.0
4 EAST COASTAL 0.0
5 NORTH 553.21
6 NORTH WEST 0.0
7 SOUTH 0.0
8 SOUTH CENTRAL 0.0
9 WEST 0.0
Please note all are Datatable how can i Get the Result

Let say your DataTable are declared as following:
var dt1 = new DataTable();
dt1.Columns.Add(new DataColumn("Id", typeof(int)));
dt1.Columns.Add(new DataColumn("Name", typeof(string)));
var dt2 = new DataTable();
dt2.Columns.Add(new DataColumn("Id", typeof(int)));
dt2.Columns.Add(new DataColumn("Name", typeof(string)));
dt2.Columns.Add(new DataColumn("Value", typeof(double)));
You can join it and get what you want with LINQ to objects:
var query = from r1 in dt1.AsEnumerable()
join r2 in dt2.AsEnumerable() on r1.Field<int>("Id") equals r2.Field<int>("Id") into r3
from r4 in r3.DefaultIfEmpty()
select new
{
Id = r1.Field<int>("Id"),
Name = r1.Field<string>("Name"),
Value = r4 == null ? 0.00 : r4.Field<double>("Value")
};
With that IEnumerable<Anonymous_Type> you can get DataTable object back, using ToDataTable<T> extension method:
public static class EnumerableToDataTableConverter
{
public static DataTable ToDataTable<T>(this IEnumerable<T> items)
{
DataTable dataTable = new DataTable(typeof(T).Name);
//Get all the properties
PropertyInfo[] Props = typeof(T).GetProperties(BindingFlags.Public | BindingFlags.Instance);
foreach (PropertyInfo prop in Props)
{
//Setting column names as Property names
dataTable.Columns.Add(prop.Name);
}
foreach (T item in items)
{
var newRow = dataTable.NewRow();
for (int i = 0; i < Props.Length; i++)
{
//inserting property values to datatable rows
newRow[Props[i].Name] = Props[i].GetValue(item, null);
}
dataTable.Rows.Add(newRow);
}
//put a breakpoint here and check datatable
return dataTable;
}
}
You can get DataTable from query with following statement:
var result = query.ToDataTable();