This is my sql command:
select
b.Brand,
count(b.Brand) as BrandCount,
SUM(a.Qty) as DeviceCount
from (
select * from DeviceList
) as a
join DeviceMaster as b
on a.DeviceMasterId = b.Id
group by b.Brand
Here is what I've tried so far:
var v1 = (from p in ghostEntities.DeviceMasters
join c in ghostEntities.DeviceLists on p.Id equals c.DeviceMasterId
select new table_Model {
Id = c.Id,
qty = c.Qty.Value,
month = c.DMonth,
brand = p.Brand,
model = p.Model,
memory = p.Memory
}).ToList();
I am getting the values form two tables but can't group them or add the values.
You should add group by into your LINQ query and use Distinct().Count() and Sum() aggregation functions:
var query = from a in ghostEntities.DeviceList
join b in ghostEntities.DeviceMaster on a.DeviceMasterId equals b.Id
group b by b.Brand into g
select new { g.Key, count =g.Select(x => x.Brand).Distinct().Count(), sum = g.Sum(x => x.Qty) };
You can find a lot of LINQ samples at https://code.msdn.microsoft.com/101-LINQ-Samples-3fb9811b , I hope it will help you.
Once you group by a table, you lose access to the fields of the other table in the join operation, a possible workaround would be:
var results = (from a in DeviceList
join b in DeviceMaster
on a.DeviceMasterId equals b.Id
group new { a, b } by new { b.Brand } into grp
select new
{
Brand = grp.Key.Brand,
BrandCount = grp.Count(),
DeviceCount = grp.Sum(x=> x.a.Qty.GetValueOrDefault())
}).ToList();
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