linq query with group - asp.net

I'm having a table which contains userId, regBy, regDate and so many..
I need a out of regDate, regBy and count(userId).
How can a query this using LINQ..

From what I understand, you want to group by two fields, regDate and regBy. In that case, the select statement looks something like this:
var myQuery = from User myUser in myContext.Users
group myUser by new { regDate = myUser.regDate , regBy = myUser.regBy } into g
select new
{
regDate = g.Key.regDate,
regBy = g.Key.regBy,
Count = g.Count()
};

Related

is there a way to get rid of DTO

I am using Entity Framework. I have the following query in which I get data using two tables Application and Employee connected by a foreign key EmployeeID in Application Table. The tables have 1-1 relationship .
Is there a way to simplify the following code and get rid of the DTO Employee1
which is the same as auto generated Employee class
public List<Employee1> GetApplicant(int ApplicationID)
{
var context = new FPSDB_newEntities();
var data = (from a in context.Applications
join e in context.Employees on a.EmployeeID equals e.EmployeeID
where
(
a.ApplicationID == ApplicationID
)
select new Employee1
{
EmployeeID = e.EmployeeID,
SecondEmail = e.SecondEmail,
EmailID = e.EmailID,
Title = e.Title,
Name = e.Name,
Rank = e.Rank,
POBox = e.POBox,
Phone = e.Phone,
JoinDate = e.JoinDate,
Status = e.Status,
DepartmentID = e.DepartmentID.Value,
NameString = e.NameString,
Department = e.Department,
ParentDept = e.ParentDept,
DepartmentAr = e.DepartmentAr,
NameAr = e.NameAr,
NameStringAr = e.NameStringAr,
TitleAr = e.TitleAr
}).ToList();
return data;
}
If you need to return list of Employees, just select e which refers to Employee and don't use Employee1 as a DTO.
public List<Employee> GetApplicant(int ApplicationID)
{
var context = new FPSDB_newEntities();
var data = (from a in context.Applications
join e in context.Employees on a.EmployeeID equals e.EmployeeID
where
(
a.ApplicationID == ApplicationID
)
select e).ToList();
return data;
}
Another way is this, which I would prefer because of readability:
public List<Employee> GetApplicant(int ApplicationID)
{
var context = new FPSDB_newEntities();
var data = context.Applications.Where(p=>p.ApplicationID == ApplicationID).Select(p=>p.Employee).ToList();
return data;
}

Getting error while inserting table in database?

i am inserting table in database using table datatype with the following code:
CREATE TYPE BackUpDoctorLocationAreaRoom AS TABLE (
[RoomId] bigint,
[AreaId] bigint,
[LocationId] bigint
);
Alter proc proc_tblBackUpDoctorInsert
(
#Id uniqueidentifier='',
#BackUpDoctorId uniqueidentifier='1323e1f4-7a93-4b45-9a9b-3840c32fd6d8',
#StartDate datetime='11/08/2012',
#EndDate datetime='11/09/2012',
#StartTime datetime='22:22:22',
#EndTime datetime='01:11:11',
#CreatedBy uniqueidentifier='acf7961c-4111-49ad-a66a-ce7f9ce131bd',
#ModifiedBy uniqueidentifier='acf7961c-4111-49ad-a66a-ce7f9ce131bd',
#createdDate datetime='11/6/12 3:09:58 AM',
#ModifiedDate datetime='11/6/12 3:09:58 AM',
#tblBackUpDoctorsForRooms BackUpDoctorLocationAreaRoom READONLY
)
as
set xact_abort on
declare #newId uniqueidentifier;
set #newId = newid();
insert into tblBackUpDoctor (Id,BackUpDoctorId,StartDate,EndDate,StartTime,EndTime,CreatedBy,ModifiedBy,
createdDate,ModifiedDate,IsActive,isdeleted) values
(#newId,
#BackUpDoctorId,
#StartDate,
#EndDate,
#StartTime,
#EndTime,
#CreatedBy,
#ModifiedBy,
#createdDate,
#ModifiedDate,
1,0)
declare #IdFortblBackUpDoctorsForRooms uniqueidentifier;
set #IdFortblBackUpDoctorsForRooms = newid();
delete from tblBackUpDoctorsForRooms where BackUpRecordId=#id and Roomid in (Select roomid from #tblBackUpDoctorsForRooms)
delete from tblbackupdoctor where id=#id
insert into tblBackUpDoctorsForRooms (BackUpRecordId,Roomid,Araeid,locationid)
Select #newId,roomid,areaid,locationid from #tblBackUpDoctorsForRooms
select #newId
This is the sp in which i am using that table.
My class file's code is :
public string InsertBackUpDoctor(ClsBackUpDoctorProp objProp, DataTable dtLocAreaRoom)
{
String ConnectionString = CCMMUtility.GetCacheForWholeApplication();
String backUpRecordId = "";
SqlParameter[] param = new SqlParameter[12];
param[0] = new SqlParameter("#Id", objProp.Id);
param[1] = new SqlParameter("#BackUpDoctorId", objProp.BackUpDoctorId);
param[2] = new SqlParameter("#StartDate", objProp.StartDate);
param[3] = new SqlParameter("#EndDate", objProp.EndDate);
param[4] = new SqlParameter("#StartTime", objProp.StartTime);
param[5] = new SqlParameter("#EndTime", objProp.EndTime);
param[6] = new SqlParameter("#CreatedBy", objProp.CreatedBy);
param[7] = new SqlParameter("#ModifiedBy", objProp.ModifiedBy);
param[8] = new SqlParameter("#createdDate", CCMMUtility.GetCurrentDateTimeByTimeZone("US Mountain Standard Time"));
param[9] = new SqlParameter("#ModifiedDate", CCMMUtility.GetCurrentDateTimeByTimeZone("US Mountain Standard Time"));
param[10] = new SqlParameter("#CurrentDate", objProp.CurrentDate);
param[11] = new SqlParameter("#tblBackUpDoctorsForRooms ", dtLocAreaRoom);
backUpRecordId = SqlHelper.ExecuteScalar(ConnectionString, "proc_tblbackupdoctorInsertBackUpDoctors", param).ToString();
return backUpRecordId;
}
and here is the error which is coming when i tries to insert :
The incoming tabular data stream (TDS) remote procedure call (RPC) protocol stream is incorrect. Table-valued parameter 12 ("#tblBackUpDoctorsForRooms"), row 0, column 0: Data type 0xF3 (user-defined table type) has a non-zero length database name specified. Database name is not allowed with a table-valued parameter, only schema name and type name are valid.
I dont know why this coming please help me..
I believe you'd have to change the way you pass your custom parameter:
Not just
param[11] = new SqlParameter("#tblBackUpDoctorsForRooms ", dtLocAreaRoom);
but rather something like
SqlParameter parameter = new SqlParameter();
parameter.ParameterName = "#tblBackUpDoctorsForRooms";
parameter.SqlDbType = System.Data.SqlDbType.Structured;
parameter.TypeName = "BackUpDoctorLocationAreaRoom";
parameter.Value = dtLocAreaRoom;
param[11] = parameter;
try
parameter.SqlDbType = System.Data.SqlDbType.Structured;
parameter.TypeName = "BackUpDoctorLocationAreaRoom";
and in the call add
backUpRecordId = SqlHelper.ExecuteScalar(ConnectionString,CommandType.StoredProcedure
"proc_tblbackupdoctorInsertBackUpDoctors", param).ToString();

How to calculate count on of table column using group by clause in linq

I'm new to linq.
In c# I'm doing as follows to get the count of one column.
SELECT DispatcherName,
ActivityType,
CONVERT(BIGINT,COUNT(ActivityType)) AS Total
FROM ACTIVITYLOG
GROUP BY DispatcherName,
ActivityType
ORDER BY Total DESC
Can any one tell m,how I can achieve the same thing using LINQ.
Update:
HI I did as follows and got the reslut.
But I'm not able to convert result to datatable.
this is how I did.
here dt is datatabe with two columns Dispatchername and ActivityType.
var query1 = from p in dt.AsEnumerable()
group p by new
{
DispatcherName = p.Field<string>("Dispatchername"),
Activity = p.Field<string>("ActivityType"),
}
into pgroup
let count = pgroup.Count()
orderby count
select new
{
Count = count,
DispatcherName = pgroup.Key.DispatcherName,
Activity = pgroup.Key.Activity
};
pls help me out asap.
from c in ACTIVITYLOG
group c by new {c.DispatcherName, c.ActivityType} into g
orderby g.Count() descending
select new { g.Key.DispatcherName, g.Key.ActivityType, Total = g.Count() }
If you want your results returned back to a DataTable, one option is to use the CopyToDataTable method.
Here's a live example: http://rextester.com/XHX48973
This method basically requires you to create a dummy table in order to use its NewRow method - the only way to create a DataRow, which is required by CopyToDataTable.
var result = dt.AsEnumerable()
.GroupBy(p => new {
DispatcherName = p.Field<string>("DispatcherName"),
Activity = p.Field<string>("ActivityType")})
.Select(p => {
var row = dummy.NewRow();
row["Activity"] = p.Key.Activity;
row["DispatcherName"] = p.Key.DispatcherName;
row["Count"] = p.Count();
return row;
})
.CopyToDataTable();
Perhaps a better way might be just fill in the rows directly, by converting to a List<T> and then using ForEach.
DataTable dummy = new DataTable();
dummy.Columns.Add("DispatcherName",typeof(string));
dummy.Columns.Add("Activity",typeof(string));
dummy.Columns.Add("Count",typeof(int));
dt.AsEnumerable()
.GroupBy(p => new { DispatcherName = p.Field<string>("DispatcherName"),
Activity = p.Field<string>("ActivityType")})
.ToList()
.ForEach(p => {
var row = dummy.NewRow();
row["Activity"] = p.Key.Activity;
row["DispatcherName"] = p.Key.DispatcherName;
row["Count"] = p.Count();
dummy.Rows.Add(row);
});
Live example: http://rextester.com/TFZNEO48009
This should do the trick:
IList<ACTIVITYLOG> allActivityLogs;
var result = (from c in allActivityLogs
select new
{
DispatcherName = c.DispatcherName,
ActivityType = c.ActivityType,
Total = c.ActivityType.Count
}).OrderByDescending(x => x.Total)
.GroupBy(x => new { x.DispatcherName, x.ActivityType });
You only need to substitute the allActivityLogs collection with the actual collection of your entities.

Group using linq return datatable

i have a linq query that returns Articles ordered by the number of tags that match the current article
e.g
current article has tags - tag1, tag2, tag3
tagged article 1 - tag1,tag2,tag3
tagged article 2 - tag1,tag2
linq i have is
DataTable query = (from row in dt.AsEnumerable()
let tags = row.Field<string>("Tags").Split(seperator, StringSplitOptions.RemoveEmptyEntries)
let count = tags.Count(t => currenttags.Contains(t))
orderby count descending
select row).CopyToDataTable();
i want to add the group by ClassName which is the article type (literature, case study, download etc)
so would be
group row by {row.Field<string>("ClassDisplayName")}
however when i add this to the query i get red sqiggles
DataTable query = (from row in dt.AsEnumerable()
group row by {row.Field<string>("ClassDisplayName")}
let tags = row.Field<string>("Tags").Split(seperator, StringSplitOptions.RemoveEmptyEntries)
let count = tags.Count(t => currenttags.Contains(t))
orderby count descending
select row).CopyToDataTable();
any ideas what i'm doing wrong?
This is the current one that works with just the order by
DataTable dt = ArticleCollection(SqlClause.ToString());
var seperator = new[] { ",", " " };
var current = dr["Tags"].ToString();
var currenttags = dr.Field<string>("Tags").Split(seperator, StringSplitOptions.RemoveEmptyEntries);
DataTable query = (from row in dt.AsEnumerable()
let tags = row.Field<string>("Tags").Split(seperator, StringSplitOptions.RemoveEmptyEntries)
let count = tags.Count(t => currenttags.Contains(t))
orderby count descending
// group row by row.Field<string>("ClassDisplayName") into g
select row).CopyToDataTable();
if (!DataHelper.DataSourceIsEmpty(query))
{
TagRepeaterOutter.DataSource = query;
TagRepeaterOutter.DataBind();
}
If you are trying to order by count, and within each value of count, group the rows by ClassDisplayName, you can try this:
DataTable query = (from row in dt.AsEnumerable()
let tags = row.Field<string>("Tags").Split(seperator, StringSplitOptions.RemoveEmptyEntries)
let count = tags.Count(t => currenttags.Contains(t))
let displayName = row.Field<string>("ClassDisplayName")
orderby count descending, displayName
select row).CopyToDataTable();
DataTable query = (from row in dt.AsEnumerable()
where (row.Field<string>("ClassDisplayName") == dr["ClassDisplayName"].ToString())
let tags = row.Field<string>("Tags").Split(seperator, StringSplitOptions.RemoveEmptyEntries)
let count = tags.Count(t => currenttags.Contains(t))
orderby count descending
select row).CopyToDataTable();
IEnumerable<DataRow> types = (from row in dt.AsEnumerable()
group row by row.Field<string>("ClassDisplayName") into g
select g.FirstOrDefault());
DataTable dtType = types.CopyToDataTable();
and then another query on the inner nested repeater
DataTable query = (from row in dt.AsEnumerable()
where (row.Field<string>("ClassDisplayName") == dr["ClassDisplayName"].ToString())
let tags = row.Field<string>("Tags").Split(seperator, StringSplitOptions.RemoveEmptyEntries)
let count = tags.Count(t => currenttags.Contains(t))
orderby count descending
select row).CopyToDataTable();
anyone have a better solution let me know

how group by in Linq with 2 Field?

how group by in Linq with 2 Field ?
(from i in info
group i by i.OrderId into g
select new { orderId = g.Key, infos = g });
not only order by with order Id but with two field like ...
group by i.orderId And i.City
how this will do?
I believe you want something like this:
var result = from i in info
group i by new { OrderId = i.OrderId, City = i.City } into g
select new { OrderId = g.Key, Infos = g };
Creating the key as an anonymous type simply allows LINQ to use the default equality comparers for all the fields of the anonymous type, which should do the job in most situations.
As a follow-up to Noldorin's answer, you can omit the field names on the anonymous type when they match the fields you're setting them to.
Example:
var result = from i in info
group i by new { i.OrderId, i.City } into g
select new { OrderId = g.Key, Infos = g };
Another follow-up to the Noldorin's and Josh Einstein's answers...OrderID will take on the entire key...which in this case is a new object with two properties, OrderID and City. If your final result set needs the OrderID to be the OrderID, then you'll need to do the following:
var result = from i in info
group i by new { i.OrderId, i.City } into g
select new { OrderId = g.Key.OrderId, Infos = g };

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