CODEWITHSUNDEEP
c#linq
TheDizzle
TheDizzle

Reputation: 1574

How would I group these items together by month only in LINQ?

I have a query that is pulling data from the database. Its grouping the items by their CheckDate. I need to turn the CheckDate which is a standard DateTime into just the month so that is grouped by month with no other dates. I can't figure out how to do that.

var query = from ech in this.dbContext.EmployeeCheckHistories
                    where ech.CompanyID == GlobalVariables.CompanyID &&
                    ech.Employees.ClientID == GlobalVariables.Client
                    group ech by ech.CheckDate into echG
                    orderby echG.Key descending
                    select echG;

Upvotes: 0

Views: 70

Answers (2)

Manoz
Manoz

Reputation: 6587

Your query-

var query = from ech in this.dbContext.EmployeeCheckHistories
                    where ech.CompanyID == GlobalVariables.CompanyID &&
                    ech.Employees.ClientID == GlobalVariables.Client
                    group ech by ech.CheckDate into echG
                    orderby echG.Key descending
                    select echG;

Could be simplified as- 

var query = this.dbContext.EmployeeCheckHistories.Where(c=> 
     c.CompanyID == GlobalVariable.CompanyID 
     && c.Employees.ClientID == GlobalVariables.ClientID).GroupBy(d=> d.CheckDate.Month);

Upvotes: 0

Frank Bryce
Frank Bryce

Reputation: 8446

I need to turn the CheckDate which is a standard DateTime into just the month

If it truly is a DateTime, then this should do the trick. Just group by the Month property on CheckDate.

var query = from ech in this.dbContext.EmployeeCheckHistories
            where ech.CompanyID == GlobalVariables.CompanyID &&
                  ech.Employees.ClientID == GlobalVariables.Client
            group ech by ech.CheckDate.Month into echG
            orderby echG.Key descending
            select echG;

If it is actually a Nullable<DateTime>, then you will need to check that the value exists, then group by Month if it does.

var query = from ech in this.dbContext.EmployeeCheckHistories
            where ech.CompanyID == GlobalVariables.CompanyID &&
                  ech.Employees.ClientID == GlobalVariables.Client &&
                  ech.CheckDate.HasValue
            group ech by ech.CheckDate.Value.Month into echG
            orderby echG.Key descending
            select echG;

Upvotes: 1

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