I have sql as below
SELECT Q.MaterialID AS MaterialID, Q.ProductID AS ProductID, QB.Quantity AS Quantity,
Q.ParameterID AS ParameterID, SUM((Q.ParameterValue * Q.Quantity)/Q.TotalTonnes) AS ParameterValue
FROM #Quality Q
INNER JOIN #QuantityBreakdown QB
ON ((Q.MaterialID = QB.MaterialID) OR (Q.MaterialID IS NULL AND QB.MaterialID IS NULL))
AND ((Q.ProductID = QB.ProductID) OR (Q.ProductID IS NULL AND QB.ProductID IS NULL))
GROUP BY Q.MaterialID, Q.ProductID, ParameterID, QB.Quantity
conversion to LINQ..... struck at ???
var enumerable = from final in (from q in qualities
from qb in quantityBreakDowns
where q.ProductID == qb.ProductID && q.MaterialID == qb.MaterialID
select new
{
q.MaterialID,
q.ProductID,
q.ParameterID,
qb.Quantity,
ParameterValue = ((q.ProductID*q.Quantity)/q.TotalTonnes)
}
)
group final by new
{
final.MaterialID,
final.ProductID,
final.ParameterID,
???
}
into finalresult select finalresult;
Is there some other good way to do this.
Thanks
Ok solved this as:
from final in
(from q in qualities
from qb in quantityBreakDowns
where q.ProductID == qb.ProductID && q.MaterialID == qb.MaterialID
select new
{
q.MaterialID,
q.ProductID,
q.ParameterID,
qb.Quantity,
ParameterValue = ((q.ActualValue*q.Quantity)/q.TotalTonnes)
}
)
group final by new
{
final.MaterialID,
final.ProductID,
final.ParameterID,
final.Quantity
}
into finalresult
select new
{
finalresult.Key.MaterialID,
finalresult.Key.ProductID,
finalresult.Key.ParameterID,
finalresult.Key.Quantity,
ActualValue = finalresult.Sum(fq => fq.ParameterValue)
};
Related
var result = (from p in db.push_notifications
join nu in db.notification_recievers on p.id equals nu.push_notification_id
join nt in db.notification_types on p.notification_type_id equals nt.id
where (p.id == pushNotificationId && p.send_criteria == criteria && nu.delete_flag == false && p.delete_flag == false && nt.delete_flag == false)
select new NotificationList
{
conferenceId = p.conference_id,
pushNotificationId = p.id,
notificationId = nt.id,
notificationType = nt.notification_type,
nottificationDate = p.created_dt_tm,
criteria = (int)p.send_criteria,
notificationMessage = p.notification_msg,
userEmail=null,
userInterests = **getInterestNamesByPushNotificationId(p.id)**,
userEvents=null
}).Distinct();
public string getInterestNamesByPushNotificationId(int id)
{
string interests = string.Empty;
var query = from i in db.interests
join pn in db.notification_recievers
on i.id equals pn.interest_id
where pn.push_notification_id == id && pn.delete_flag == false
select new
{
name = i.name
};
foreach (var intr in query.Distinct())
{
if (interests == "")
{
interests = intr.name;
}
else
{
interests = interests + ", " + intr.name;
}
}
return interests;
}
this is throwing me error
LINQ to Entities does not recognize the method 'System.String
getInterestNamesBy PushNotification(Int32)' method, and this method
cannot be translated into a store expression.
The Entity Framework is trying to execute your LINQ clause on the SQL side, obviously there is no equivalent to 'getInterestNamesBy PushNotification(Int32)' from a SQL perspective.
You need to force your select to an Enumerable and then reselect your object using the desired method.
Not ideal but something like this should work - (not tested this so be nice).
var result = (from p in db.push_notifications
join nu in db.notification_recievers on p.id equals nu.push_notification_id
join nt in db.notification_types on p.notification_type_id equals nt.id
where (p.id == pushNotificationId && p.send_criteria == criteria && nu.delete_flag == false && p.delete_flag == false && nt.delete_flag == false)
select new { p=p, nu = nu, nt = nt }).AsEnumerable().Select( x => new NotificationList()
{
conferenceId = x.p.conference_id,
pushNotificationId = x.p.id,
notificationId = x.nt.id,
notificationType = x.nt.notification_type,
nottificationDate = x.p.created_dt_tm,
criteria = (int)x.p.send_criteria,
notificationMessage = x.p.notification_msg,
userEmail=null,
userInterests = getInterestNamesByPushNotificationId(x.p.id),
userEvents=null
}).Distinct();
i have done it this way
In my model
using (NotificationService nService = new NotificationService())
{
modelView = nService.DetailsOfNotifications(pushNotificationId, criteriaId).Select(x => new NotificationViewModelUI(x.conferenceId, x.pushNotificationId, x.notificationId, x.notificationType, x.nottificationDate, x.criteria, x.notificationMessage, x.userEmail, nService.getInterestNamesByPushNotificationId(x.pushNotificationId), nService.getIEventTitlesByPushNotificationId(x.pushNotificationId))).ToList();
}
public NotificationViewModelUI(int conferenceId, int pushNotificationId, int notificationId, string notificationType, DateTime dateTime, int criteria, string nMessage, string emailId = null, string interestNames = null, string eventTitles = null)
{
this.conferenceId = conferenceId;
this.pushNotificationId = pushNotificationId;
this.notificationId = notificationId;
this.notificationType = notificationType;
this.notificationDate = dateTime;
this.sendCriteria = (NotificationCriteria)criteria;
this.notificationMessage = nMessage;
this.emailId = NotificationCriteria.SpecificUser.Description() +"... "+ emailId;
this.interestNames = NotificationCriteria.UserByInterests.Description() + "... " + interestNames;
this.eventTitles = NotificationCriteria.UserByEvents.Description() + "... " + eventTitles;
}
Ii just want to make search functionality with linq with multiple ColumnNames that stored to session variable. I'm using one method:
public void FillGrid(string CommandName,string ColumnName, string SearchText)
That has three string variable that stores session value.
Now I just want to pass ColumnName with this query:
var query1 = (from p in db.Posts
join c in db.Categories on p.Category_id equals c.Id
join u in db.Users on p.User_id equals u.Id
where (p.ToUser_id == user_id || p.ToUser_id == null) && p.User_id != user_id
orderby p.Sent_Datetime descending
select new
{
Id = p.Id,
Title = p.Title,
Publisher = u.First_name + " " + u.Last_name,
ToUser = p.ToUser_id,
PublishDate = p.Sent_Datetime,
IsFile = p.IsFileAttached,
CategoryName = c.Category_name,
status_name = (from s in db.Status where (s.Id == p.status_id) select s.status_name).FirstOrDefault(),
Group_name = (from g in db.Groups where (g.Id == p.group_id) select g.Group_name).FirstOrDefault(),
FileSize = p.TotalFileSize,
ColumnName = Sesssion["ColumnName"].ToString()
}).Where(q => q.ColumnName.Contains(SearchText));
However, ColumnName does not give any text or it may be not part of this query i have to manually give column name because.
for multiple column i have, so i can not use this statement like:
.Where(q => q.Tile.Contains(SearchText));
this query works fine with single column. but there is multiple column i have so i have to set q.ColumnName from outer side.
I would do an extension method for that kind of things, building an expression for your predicate.
public static class Helper
{
public static IQueryable<T> FilterForColumn<T>(this IQueryable<T> queryable, string colName, string searchText)
{
if (colName != null && searchText != null)
{
var parameter = Expression.Parameter(typeof(T), "m");
var propertyExpression = Expression.Property(parameter, colName);
var searchExpression = Expression.Constant(searchText);
var containsMethod = typeof(string).GetMethod("Contains", new[] { typeof(string) });
var body = Expression.Call(propertyExpression, containsMethod, searchExpression);
var predicate = Expression.Lambda<Func<T, bool>>(body, new[] { parameter });
return queryable.Where(predicate);
}
else
{
return queryable;
}
}
}
usage in your case
var query1 = (from p in db.Posts
join c in db.Categories on p.Category_id equals c.Id
join u in db.Users on p.User_id equals u.Id
where (p.ToUser_id == user_id || p.ToUser_id == null) && p.User_id != user_id
orderby p.Sent_Datetime descending
select new
{
Id = p.Id,
Title = p.Title,
Publisher = u.First_name + " " + u.Last_name,
ToUser = p.ToUser_id,
PublishDate = p.Sent_Datetime,
IsFile = p.IsFileAttached,
CategoryName = c.Category_name,
status_name = (from s in db.Status where (s.Id == p.status_id) select s.status_name).FirstOrDefault(),
Group_name = (from g in db.Groups where (g.Id == p.group_id) select g.Group_name).FirstOrDefault(),
FileSize = p.TotalFileSize,
}).FilterForColumn(Sesssion["ColumnName"].ToString(), SearchText);
I need to consider multiple conditions to get value.
i mean if all conditions true that must give me a filtered answer.
Or one of them is true,rest are false...
so i need to write all possibilities??
if(a&b&c&d) else if(a&b&c) else if(a&c&d) else if(b&c&d) else if(a&b) else if (a&c)...etc ?? :))) Is there a shorter way to do this?
public List<ProductReqNoDate> GetRequestsQuery(string departmant, int reqStateID, string firstDate, string lastDate, string productName)
{
var db = new requestDBEntities();
bool dp = !string.IsNullOrEmpty(departmant);
bool pr = !string.IsNullOrEmpty(productName);
bool tm = !string.IsNullOrEmpty(firstDate) && !string.IsNullOrEmpty(lastDate);
bool rs = reqStateID > 0 ? true : false;
var query = (from r in db.requests
select new ProductReqNoDate
{
departmant = r.departmant,
reqNo = r.reqNo,
reqDate = r.reqDate,
productName = (from p in db.products where p.reqNo == r.reqNo select p.productName).FirstOrDefault()
}).ToList();
if (dp & pr & tm & rs)
{
var rState = (from ta in db.reqStates
where ta.reqStateID == reqStateID && ta.isActive == true
select ta.reqNo).ToList();
var prName = (from p in db.products where p.productName.Contains(productName) select p.reqNo).ToList();
DateTime dtfirstDate = Convert.ToDateTime(firstDate);
DateTime dtlastDate = Convert.ToDateTime(lastDate);
return query.Where(
r => rState.Contains(r.reqNo) //find by Request State
&& r.departmant == departmant //find by Departmant
&& (r.reqDate >= dtfirstDate && r.reqDate <= dtlastDate) //find by Date
&& prName.Contains(r.reqNo) //Find By Product Name
).ToList();
}
else if (dp & pr & tm) { /*return query.Where(...} */}
else if (pr & tm & rs) { /*return query.Where(...} */}
else if (dp & pr && rs) { /*return query.Where(...} */}
else if (dp & pr) { /*return query.Where(...} */}
//else if ...etc
}
Just add one Where condition at a time
public List<ProductReqNoDate> GetRequestsQuery(string departmant, int reqStateID, string firstDate, string lastDate, string productName)
{
var db = new requestDBEntities();
bool dp = !string.IsNullOrEmpty(departmant);
bool pr = !string.IsNullOrEmpty(productName);
bool tm = !string.IsNullOrEmpty(firstDate) && !string.IsNullOrEmpty(lastDate);
bool rs = reqStateID > 0 ? true : false;
var query = (from r in db.requests
select new ProductReqNoDate
{
departmant = r.departmant,
reqNo = r.reqNo,
reqDate = r.reqDate,
productName = (from p in db.products where p.reqNo == r.reqNo select p.productName).FirstOrDefault()
}).AsQueryable(); //AsQueryable is not always needed, but it shouldn't hurt and I don't feel like checking for this example.
if (dp)
{
query = query.Where(q => /*condition*/);
}
if (pr)
{
query = query.Where(q => /*condition*/);
}
if (tm)
{
query = query.Where(q => /*condition*/);
}
if (rs)
{
query = query.Where(q => /*condition*/);
}
return query.ToList();
}
You can build an expression with Expression.And like:
private Expression<Func<Request, bool>> GetPredicate(FilterDto filter)
{
Expression<Func<Request, bool>> predicate = r => r.ID == r.ID;
if (filter.Department.HasValue)
predicate = predicate.And(r => r.Department == filter.Department.Value);
if (filter.FirstDate.HasValue)
predicate = predicate.And(r => (r.reqDate >= filter.FirstDate.Value));
if (filter.LastDate.HasValue)
predicate = predicate.And(r => (r.reqDate <= filter.LastDate.Value));
/* ... */
return predicate;
}
Note: I put r => r.ID == r.ID here as first expression, just to have an expression to start with. This snippet does not fully cover your code, but I think it is enough as an example.
Use the expression in return query.Where(expression).ToList().
SELECT StudentHistoryId, StudentId, Grade, CreatedAt, ModifiedAt, ModifiedBy, Active
FROM TABLENAME TN
INNER JOIN ( SELECT StudentId, MAX(ModifiedAt) AS ModifiedAt FROM TABLENAME GROUP BY StudentId) M
ON TN.StudentId = M.StudentId AND TN.ModifiedAt = M.ModifiedAt
Here's a direct translaton:
var subquery = from tn in dc.TABLENAME
group tn by tn.StudentId into g
select new { StudentId = g.Key, ModifiedAt = g.Max(x => x.ModifiedAt) };
var query = from tn in dc.TABLENAME
join m in subquery
on new { tn.StudentId, tn.ModifiedAt }
equals new { m.StudentId, m.ModifiedAt }
select new
{
tn.StudentHistoryId,
tn.StudentId,
tn.Grade,
tn.CreatedAt,
tn.ModifiedAt,
tn.ModifiedBy,
tn.Active
};
In her book Entity Framework Julie Lerman recommends using nested queries in preference to joins (scroll back a couple of pages).
In her example see populates 1 field this way, but what id you want to populate 2?
I have an example here where I would prefer to populate the Forename and Surname with the same nested query rather than 2 separate ones. I just need to know the correct syntax to do this.
public static List<RequestInfo> GetRequests(int _employeeId)
{
using (SHPContainerEntities db = new SHPContainerEntities())
{
return db.AnnualLeaveBookeds
.Where(x => x.NextApproverId == _employeeId ||
(x.ApproverId == _employeeId && x.ApprovalDate.HasValue == false))
.Select(y => new RequestInfo
{
AnnualLeaveDate = y.AnnualLeaveDate,
Forename = (
from e in db.Employees
where e.EmployeeId == y.EmployeeId
select e.Forename).FirstOrDefault(),
Surname = (
from e in db.Employees
where e.EmployeeId == y.EmployeeId
select e.Surname).FirstOrDefault(),
RequestDate = y.RequestDate,
CancelRequestDate = y.CancelRequestDate,
ApproveFlag = false,
RejectFlag = false,
Reason = string.Empty
})
.OrderBy(x => x.AnnualLeaveDate)
.ToList();
}
}
There's nothing wrong with your query, but you can write it in a way that is much simpler, without the nested queries:
public static List<RequestInfo> GetRequests(int employeeId)
{
using (SHPContainerEntities db = new SHPContainerEntities())
{
return (
from x in db.AnnualLeaveBookeds
where x.NextApproverId == employeeId ||
(x.ApproverId == employeeId && x.ApprovalDate == null)
orderby x.AnnualLeaveDate
select new RequestInfo
{
AnnualLeaveDate = x.AnnualLeaveDate,
Forename = x.Employee.Forename,
Surname = x.Employee.Surname,
RequestDate = x.RequestDate,
CancelRequestDate = x.CancelRequestDate,
ApproveFlag = false,
RejectFlag = false,
Reason = string.Empty
}).ToList();
}
}
See how I just removed your from e in db.Employees where ... select e.Forename) and simply replaced it with x.Employee.Forename. When your database contains the correct foreign key relationships, the EF designer will successfully generate a model that contain an Employee property on the AnnualLeaveBooked entity. Writing the query like this makes it much more readable.
I hope this helps.
try this
using (SHPContainerEntities db = new SHPContainerEntities())
{
return db.AnnualLeaveBookeds
.Where(x => x.NextApproverId == _employeeId ||
(x.ApproverId == _employeeId && x.ApprovalDate.HasValue == false))
.Select(y =>
{
var emp = db.Emplyees.Where(e => e.EmployeeId == y.EmployeeId);
return new RequestInfo
{
AnnualLeaveDate = y.AnnualLeaveDate,
Forename = emp.Forename,
Surname = emp.Surname,
RequestDate = y.RequestDate,
CancelRequestDate = y.CancelRequestDate,
ApproveFlag = false,
RejectFlag = false,
Reason = string.Empty
};
).OrderBy(x => x.AnnualLeaveDate).ToList();
}