I have following result set. How to get latest History records which meets criteria : Status = 'A' in linq ? Grouping is done on Entity Id and Records will be sorted descending on History Id
History ID Entity ID Status
2969 6957 I
2968 6957 A
2967 6957 A
2303 6957 I
1000 6958 A
55 6959 A
50 6959 I
45 6960 I
40 6960 A
Results should give me
History ID Entity ID Status
1000 6958 A
55 6959 A
first group by entity and get the "latest" records for each group. Finally check for a status of A:
histories.GroupBy(h => h.EntityId)
.Select(g => g.OrderByDescending(h => h.HistoryID)
.First())
.Where(h => h.Status == "A");
Related
i have one table like this
id
version
secondId
1
1
1000
1
2
1000
1
3
1000
2
1
1001
2
2
1001
2
3
1001
verion and id are composite key . i want to add auto increment secondId . for all id , secondId is same but version is diffrent. i dont konw how to handle this in code first EF .
i write blow code in dbcontext file
modelBuilder.Entity<user>().HasKey(e => new { e.Id, e.Version });
modelBuilder.Entity<user>().HasAlternateKey(q => new { q.Version, q.SecondId });
modelBuilder.Entity<user>().Property(q => q.SecondId).UseIdentityAlwaysColumn();
modelBuilder.Entity<user>().Property(q => q.SecondId).HasIdentityOptions(1000);
# Transaction Id Amount Status
1 AA001 100 pending
2 AA001 100 success
3 AA002 200 pending
On above data AA001 - having both pending & success AA002 have only pending
So expected to get as below
# Transaction Id Amount Status
2 AA001 100 success
3 AA002 200 pending
How to apply Aggregation?
Condition:
- if a transaction have both pending and success status record return only success record
- if a transaction have only pending return pending record
In theory you can sort the way you want , and a rank to each row. Pick the rank = 1 , so you pick only one row for a unique combination of transaction id and amount.
Can anyone suggest a linq query for the below requirement.
There is a Checkbox on the form..when we click on it...As per the below datatable it has to be grouped according to ItemCode,Sum(SoldQty), StockInHand,LatestRecordValueOfSales, Amount, Description.
You can't group. the following columns
solddate - show the latest sold date
department
category
ItemCode Description UOM SoldQty Stock in Hand SellPrice Amount
---------------------------------------------------------------
100 Paracetamol 200MG UOM1 5 -5 3 8 0 100 1/21/2013 MEAT INDIAN BEAF
100 Paracetamol 200MG UOM1 5 -5 3 8 0 100 1/21/2013 MEAT INDIAN BEAF
200 frozen meat Kilograms 0.005 88.19 4 4.01 0 200 1/21/2013 OTHERS INDIAN BEAF
200 frozen meat Kilograms 0.044 88.19 4 4.04 0 200 1/21/2013 OTHERS INDIAN BEAF
100 Paracetamol 200MG UOM1 5 -5 3 8 0 100 1/22/2013 MEAT INDIAN BEAF
200 frozen meat Kilograms 0.054 88.19 4 4.05 0 200 1/22/2013 OTHERS INDIAN BEAF
200 frozen meat Kilograms 0.055 88.19 4 4.06 0 200 1/22/2013 OTHERS INDIAN BEAF
========================================================================
General query
var resQuery = from i in someQueryable
group i by new {i.groupProperty1, i.groupProperty2} into g
select new
{
Property1 = g.Key.Property1,
Property2 = g.Key.Property2
Total = g.Sum(p => p.SumProperty),
/// other properties
};
For your example data it could be like:
var resQuery = from i in dbContext.Items
group i by new{ i.ItemCode, i.Description, i.UOM} into g
select new
{
ItemCode = g.Key.ItemCode,
TotalSold = g.Sum(p => p.SoldQty),
Description = g.Key.Description,
UOM =g.Key.UOM
/// other properties
};
Try example on Ideone: http://ideone.com/xXwgoG
Similar questions asked on SO many times:
Linq Objects Group By & Sum
LINQ Lambda Group By with Sum
Multiple group by and Sum LINQ
Below is my code and it works fine but only for the first row the soldqty and Amount values are getting doubled.while other rows data is fine.I am not able to understand why only the first row data Sum(SoldQty) is getting doubled.
decimal? SoldQty, stockinhand,SellPrice,Amount,CostPrice;
string ItemCode, Description,UOM,BarCode,SoldDate,Department,Category,User;
var resQuery = from row in dtFilter.AsEnumerable()
group row by row.Field<string>("Item Code") into g
select dtFilter.LoadDataRow(new object[]
{
ItemCode=g.Key,
Description=g.Select(r=>r.Field<string>("Description")).First<string>(),
UOM=g.Select(r=>r.Field<string>("UOM")).First<string>(),
SoldQty = g.Sum(r => r.Field<decimal?>("Sold Qty")).Value,
stockinhand=g.Select(r=>r.Field<decimal?>("Stock in Hand")).First<decimal?>(),
SellPrice=g.Select(r=>r.Field<decimal?>("Sell Price")).First<decimal?>(),
Amount = g.Sum(r => r.Field<decimal?>("Amount")).Value,
CostPrice = g.Sum(r => r.Field<decimal?>("Cost Price")).Value,
BarCode=g.Select(r=>r.Field<string>("Barcode")).First<string>(),
SoldDate=g.Select(r=>r.Field<string>("SoldDate")).Last<string>(),
Department=g.Select(r=>r.Field<string>("Department")).First<string>(),
Category=g.Select(r=>r.Field<string>("Category")).First<string>(),
User=g.Select(r=>r.Field<string>("User")).First<string>(), }, false);
I would like to create a Linq query that compares date from multiple rows in a single table.
The table consists of data that polls a web-services for balance data for account. Unfortunately the polling interval is not a 100% deterministic which means there can be 0-1-more entries for each account per day.
For the application i would need this data to be reformatted in a certain formatted (see below under output).
I included sample data and descriptions of the table.
Can anybody help me with a EF Linq query that will produce the required output?
table:
id The account id
balance The available credits in the account at the time of the measurement
create_date The datetime when the data was retrieved
Table name:Balances
Field: id (int)
Field: balance (bigint)
Field: create_date (datetime)
sample data:
id balance create_date
3 40 2012-04-02 07:01:00.627
1 55 2012-04-02 13:41:50.427
2 9 2012-04-02 03:41:50.727
1 40 2012-04-02 16:21:50.027
1 49 2012-04-02 16:55:50.127
1 74 2012-04-02 23:41:50.627
1 90 2012-04-02 23:44:50.427
3 3 2012-04-02 23:51:50.827
3 -10 2012-04-03 07:01:00.627
1 0 2012-04-03 13:41:50.427
2 999 2012-04-03 03:41:50.727
1 50 2012-04-03 15:21:50.027
1 49 2012-04-03 16:55:50.127
1 74 2012-04-03 23:41:50.627
2 -10 2012-04-03 07:41:50.727
1 100 2012-04-03 23:44:50.427
3 0 2012-04-03 23:51:50.827
expected output:
id The account id
date The data component which was used to produce the date in the row
balance_last_measurement The balance at the last measurement of the date
difference The difference in balance between the first- and last measurement of the date
On 2012-04-02 id 2 only has 1 measurement which sets the difference value equal to the last(and only) measurement.
id date balance_last_measurement difference
1 2012-04-02 90 35
1 2012-04-03 100 10
2 2012-04-02 9 9
2 2012-04-03 -10 -19
3 2012-04-02 3 -37
3 2012-04-03 0 37
update 2012-04-10 20:06
The answer from Raphaël Althaus is really good but i did make a small mistake in the original request. The difference field in the 'expected output' should be either:
the difference between the last measurement of the previous day and the last measurement of the day
if there is no previous day then first measurement of the day should be used and the last measurement
Is this possible at all? It seems to be quite complex?
I would try something like that.
var query = db.Balances
.OrderBy(m => m.Id)
.ThenBy(m => m.CreationDate)
.GroupBy(m => new
{
id = m.Id,
year = SqlFunctions.DatePart("mm", m.CreationDate),
month = SqlFunctions.DatePart("dd", m.CreationDate),
day = SqlFunctions.DatePart("yyyy", m.CreationDate)
}).ToList()//enumerate there, this is what we need from db
.Select(g => new
{
id = g.Key.id,
date = new DateTime(g.Key.year, g.Key.month, g.Key.day),
last_balance = g.Select(m => m.BalanceValue).LastOrDefault(),
difference = (g.Count() == 1 ? g.First().BalanceValue : g.Last().BalanceValue - g.First().BalanceValue)
});
Well, a probable not optimized solution, but just see if it seems to work.
First, we create a result class
public class BalanceResult
{
public int Id { get; set; }
public DateTime CreationDate { get; set; }
public IList<int> BalanceResults { get; set; }
public int Difference { get; set; }
public int LastBalanecResultOfDay {get { return BalanceResults.Last(); }}
public bool HasManyResults {get { return BalanceResults != null && BalanceResults.Count > 1; }}
public int DailyDifference { get { return HasManyResults ? BalanceResults.Last() - BalanceResults.First() : BalanceResults.First(); } }
}
then we change a little bit our query
var query = db.Balances
.GroupBy(m => new
{
id = m.Id,
year = SqlFunctions.DatePart("mm", m.CreationDate),
month = SqlFunctions.DatePart("dd", m.CreationDate),
day = SqlFunctions.DatePart("yyyy", m.CreationDate)
}).ToList()//enumerate there, this is what we need from db
.Select(g => new BalanceResult
{
Id = g.Key.id,
CreationDate = new DateTime(g.Key.year, g.Key.month, g.Key.day),
BalanceResults = g.OrderBy(l => l.CreationDate).Select(l => l.BalanceValue).ToList()
}).ToList();
and finally
foreach (var balanceResult in balanceResults.ToList())
{
var previousDayBalanceResult = balanceResults.FirstOrDefault(m => m.Id == balanceResult.Id && m.CreationDate == balanceResult.CreationDate.AddDays(-1));
balanceResult.Difference = previousDayBalanceResult != null ? balanceResult.LastBalanecResultOfDay - previousDayBalanceResult.LastBalanecResultOfDay : balanceResult.DailyDifference;
}
as indicated, performance (use of dictionaries, for example), code readability should of course be improved, but... that's the idea !
I have a dataset that looks like this:
Date
Category
Rate
Quantity
There will be 0 or 1 row for each Category for any given Date.
What is a good way to get this data into a summary type of view?
For example:
Date
Category1_Rate
Category2_Rate
Category3_Rate
Category4_Rate
I have a fixed number of Categories.
I'm using linq.
Here is an example. If I have this data:
Date Category Rate Quantity
1/1/12 toys 15 12
1/1/12 games 20 20
1/1/12 dvds 18 30
1/2/12 toys 19 13
1/2/12 dvds 20 17
I want to produce a summary that looks like this:
Date toys_rate games_rate dvds_rate
1/1/12 15 20 18
1/2/12 19 null 20
Possibly something like this
var summarydata =
from r in table
group r by r.Date into g
select new
{
Date = g.Key,
ToysRate = g.Where(e=> e.Category == "toys").Count() > 0 ?
(int?)g.Where(e=> e.Category == "toys").First().Rate : null,
GamesRate = g.Where(e=> e.Category == "games").Count() > 0 ?
(int?)g.Where(e=> e.Category == "games").First().Rate : null,
DvdsRate = g.Where(e=> e.Category == "dvds").Count() > 0 ?
(int?)g.Where(e=> e.Category == "dvds").First().Rate : null
};
Note I haven't tested this as I don't current have access to a C# environment.
EDIT - Added nullable int casts to properly set the type of the various rate fields in the resulting anonymous type.