I have the following SQL script that gives me the results i'm after , i'm having trouble replicating the full join and the count distinct on the activities count:
select ActivityCount,ActivityComplete, ImagePath, SubjectTitle from
(select
Count(Distinct(Act.[ActivityID])) as ActivityCount,
Sum(Case when (([OutcomeID] = 1 or [OutcomeID] = 3) and AOU.ActivityUserID=1 ) Then 1 Else 0 End) As ActivityComplete,
Sub.[SubjectImageName] as ImagePath,
Sub.SubjectTitle as SubjectTitle
from [dbo].[UserActivityOutcome] AOU
full join Activity Act on Act.[ActivityID] = AOU.[ActivityID]
left join Category Cat on Act.[CategoryID] = Cat.[CategoryID]
left join Subject Sub on Cat.[SubjectID] = Sub.[SubjectID]
group by Sub.SubjectTitle, Sub.[SubjectImageName]
) as x
results:
</head>
<body><div class="spacer"><table id="t1"><tr><td class="typeheader" colspan="4">Result Set (2 items)</td></tr><tr><th title="System.Int32">ActivityCount</th><th title="System.Int32">ActivityComplete</th><th title="System.String">ImagePath</th><th title="System.String">SubjectTitle</th></tr><tr><td class="n">25</td><td class="n">3</td><td>Subject 1.png</td><td>Subject 1</td></tr><tr><td class="n">1</td><td class="n">1</td><td>Subject 2.png</td><td>Subject 2</td></tr><tr><td title="Total=26
Average=13" class="columntotal">26</td><td title="Total=4
Average=2" class="columntotal">4</td><td title="Totals" class="columntotal"></td><td title="Totals" class="columntotal"></td></tr></table></div></body>
</html>
my linq looks like this:
from x in (
(from Act in Activities
join AOU in UserActivityOutcomes on Act.ActivityID equals AOU.ActivityID into AOU_join
from AOU in AOU_join.DefaultIfEmpty()
join ActNA in Activities on AOU.ActivityID equals ActNA.ActivityID into ActNA_join
from ActNA in ActNA_join.DefaultIfEmpty()
join Cat in Categories on AOU.Activity.CategoryID equals Cat.CategoryID into Cat_join
from Cat in Cat_join.DefaultIfEmpty()
join Sub in Subjects on Cat.SubjectID equals Sub.SubjectID into Sub_join
from Sub in Sub_join.DefaultIfEmpty()
group new {Sub, AOU, Act,ActNA} by new {
Sub.SubjectTitle,
Sub.SubjectImageName
} into g
select new {
ActivityCount = g.Distinct().Count(), //g.Count(),
ActivityComplete = g.Sum(p => (
(p.AOU.OutcomeID == 1 ||
p.AOU.OutcomeID == 3)&&
p.AOU.ActivityUserID == 23 ? 1 : 0)),
ImagePath = g.Key.SubjectImageName,
SubjectTitle = g.Key.SubjectTitle
}))
select new {
x.ActivityCount,
x.ActivityComplete,
x.ImagePath,
x.SubjectTitle
}
LINQ full outer join is tricky. The only way it could be simulated is by union of left outer join and right antijoin. Here is IMO the LINQ equivalent of your SQL query:
var query =
// AOU full join Act
(from e in (from AOU in UserActivityOutcomes
join Act in Activities on AOU.ActivityID equals Act.ActivityID into Act_join
from Act in Act_join.DefaultIfEmpty()
select new { AOU, Act })
.Concat
(from Act in Activities
join AOU in UserActivityOutcomes on Act.ActivityID equals AOU.ActivityID into AOU_join
from AOU in AOU_join.DefaultIfEmpty()
where AOU == null
select new { AOU, Act })
let AOU = e.AOU
let Act = e.Act
// left join Cat
join Cat in Categories on Act.CategoryID equals Cat.CategoryID into Cat_join
from Cat in Cat_join.DefaultIfEmpty()
// left join Sub
join Sub in Subjects on Cat.SubjectID equals Sub.SubjectID into Sub_join
from Sub in Sub_join.DefaultIfEmpty()
group new { Sub, AOU, Act } by new { Sub.SubjectTitle, Sub.SubjectImageName } into g
select new
{
ActivityCount = g.Where(e => e.Act != null).Select(e => e.Act.ActivityID).Distinct().Count(),
ActivityComplete = g.Sum(e => (e.AOU.OutcomeID == 1 || e.AOU.OutcomeID == 3) && e.AOU.ActivityUserID == 1 ? 1 : 0),
ImagePath = g.Key.SubjectImageName,
SubjectTitle = g.Key.SubjectTitle
};
Related
I have the following query that I would like to translate to linq.
SELECT
SUM(Credits.CreditAmount)
,Transactions.Id
,Person.FullName
,Person.Id
FROM
Person
JOIN
Transactions
ON Person.AccountId = Transactions.AccountId
JOIN Credits
ON Transactions.Id = Credits.TransactionId
WHERE
Person.Type = 'AccountHolder'
AND Person.Status = 'Active'
AND Transactions.CancelledDate IS NULL
AND Credits.CancelledDate IS NULL
GROUP BY Transactions.AccountId, Person.FullName, Person.Id
HAVING SUM(Credits.CreditAmount) > 20
This is what I came up with. It's an absolute pig... The SQL it generates must be awful.
var query = from p in Person
join t in Transactions
on p.AccountId equalas t.AccountId
join c in Credits
on t.TransactionId = c.TransactionId
where p.Status == "Active" &&
p.Type = "AccountHolder" &&
t.CancelledDate == null &&
c.CancelledDate == null
group new { c.CreditAmount, t.AccountId, p.FullName, p.Id } by new { t.AccountId, p.FullName, p.SSN } into grp
let sumC = grp.Select(x => x.CreditAmount).Sum()
select new
{
TotalCredit = sumC,
AccountId = grp.Key.AccountId,
FullName = grp.Key.FullName,
Id = grp.Key.Id
};
query.Where(p => p.TotalServiceCredit > 20);
The SQL query runs in approximately 3 seconds but I have yet to find the patience to let the Linq query finish. I was wondering if there is something different I should be doing to accomplish this "group, sum, having" query I'm trying to write? Is there something I can do to help Linq generate more performat SQL?
UPDATE
Turns out sgmoore had the right idea. The key to the performance issue was in his answer.
The difference between this
let sumC = grp.Select(x => x.CreditAmount).Sum()
and this
TotalCredit = grp.Sum(x => x.CreditAmount)
was the difference between a query that finishes and one that does not.
See my revised LINQ query below which completes in about the same time as the SQL (5.3 seconds for SQL vs 5.6 seconds for LINQ).
var query = from p in Person
join t in Transactions
on p.AccountId equalas t.AccountId
join c in Credits
on t.TransactionId = c.TransactionId
where p.Status == "Active" &&
p.Type = "AccountHolder" &&
t.CancelledDate == null &&
c.CancelledDate == null
group new { c.CreditAmount, t.AccountId, p.FullName, p.Id } by new { t.AccountId, p.FullName, p.SSN } into grp
select new
{
TotalCredit = grp.Sum(x => x.CreditAmount),
AccountId = grp.Key.AccountId,
FullName = grp.Key.FullName,
Id = grp.Key.Id
};
query.Where(p => p.TotalServiceCredit > 20);
Thanks for all your help!
I don't disagree with WEI_DBA's comment but if you need to do this, then you might find it easier to break this into several queries, eg
var query1 = from p in Person
join t in Transactions on p.AccountId equals t.AccountId
join c in Credits on t.TransactionId equals c.TransactionId
where p.Status == "Active" &&
p.Type = "AccountHolder" &&
t.CancelledDate == null &&
c.CancelledDate == null
select new { c.CreditAmount, t.AccountID, p.FullName, p.Id};
var query2 = (from p in query1
group p by new { p.AccountId, p.FullName, p.Id } into grp
select new
{
TotalCredit = grp.Sum(x => x.CreditAmount),
AccountId = grp.Key.AccountId,
FullName = grp.Key.FullName,
Id = grp.Key.Id
};
var query3 = (from p in query2 where p.TotalCredit > 20 select p);
Then you can let LINQ combine this into one sql command.
As always, it is a good idea to check and verify the actual TSQL generated.
How do i change the training events into a left outer join in training events im very basic at linq so excuse my ignorance its not retrieve records that don't have any trainnevent reference attached to it
var q = from need in pamsEntities.EmployeeLearningNeeds
join Employee e in pamsEntities.Employees on need.EmployeeId equals e.emp_no
join tevent in pamsEntities.TrainingEvents on need.TrainingEventId equals tevent.RecordId
where need.EmployeeId == employeeId
where need.TargetDate >= startdate
where need.TargetDate <= enddate
orderby need.TargetDat
It's best to use where in combination with DefaultIfEmpty.
See here: LEFT JOIN in LINQ to entities?
var query2 = (
from users in Repo.T_Benutzer
from mappings in Repo.T_Benutzer_Benutzergruppen.Where(mapping => mapping.BEBG_BE == users.BE_ID).DefaultIfEmpty()
from groups in Repo.T_Benutzergruppen.Where(gruppe => gruppe.ID == mappings.BEBG_BG).DefaultIfEmpty()
//where users.BE_Name.Contains(keyword)
// //|| mappings.BEBG_BE.Equals(666)
//|| mappings.BEBG_BE == 666
//|| groups.Name.Contains(keyword)
select new
{
UserId = users.BE_ID
,UserName = users.BE_User
,UserGroupId = mappings.BEBG_BG
,GroupName = groups.Name
}
);
var xy = (query2).ToList();
Which is equivalent to this select statement:
SELECT
T_Benutzer.BE_User
,T_Benutzer_Benutzergruppen.BEBG_BE
-- etc.
FROM T_Benutzer
LEFT JOIN T_Benutzer_Benutzergruppen
ON T_Benutzer_Benutzergruppen.BEBG_BE = T_Benutzer.BE_ID
LEFT JOIN T_Benutzergruppen
ON T_Benutzergruppen.ID = T_Benutzer_Benutzergruppen.BEBG_BG
Need to convert this sql query to LINQ
SELECT *
FROM
parcels p
LEFT JOIN leases l ON p.parcels_pk = l.parcels_fk
WHERE
l.parcels_fk IS NULL
AND p.parcels_pk NOT IN (SELECT parcels_fk FROM application_parcels)
ORDER BY parcel
tried this:
var qry = from p in db.Parcels
join l in db.Leases on p.Id equals l.pk_parcel
where l.pk_parcel == null
&& !(from ap in db.ApplicationParcels
select ap.ParcelId).Contains(p.Id)
orderby p.Name
// SELECT * FROM parcels
var result = from p in parcels
// LEFT JOIN leases ON p.parcels_pk = l.parcels_fk
join llj in leases on p.parcels_pk equals llj.parcels_fk into lj
from l in lj.DefaultIfEmpty()
// WHERE l.parcels_fk IS NULL
where l.parcels_fk == null
// AND p.parcels_pk NOT IN (...)
&& !application_parcels.Any(x => x.parcels_fk == p.parcels_pk)
// ORDER BY [p.]parcel
order by p.parcel
select new { parcel = p, lease = l };
Assuming i have your schema correct.
But in the future:
First supply what you've tried (show an effort).
Have a look at LINQPad, it's very helpful.
How to convert INNER JOIN and LEFT JOIN in the following SQL query to LINQ to SQL? Thanks!
SELECT transactions.postdate,
transactions.clientkey AS TransClientKey,
transactions.type AS TransType,
clients.clientno,
Isnull(clients.nostmt, 0) AS CliNoStmt,
Isnull(aging.nostmt, 0) AS AgeNoStmt,
pmtchecks.*
FROM ((pmtchecks
INNER JOIN transactions
ON pmtchecks.transkey = transactions.transkey)
INNER JOIN clients
ON transactions.clientkey = clients.clientkey)
LEFT JOIN aging
ON ( transactions.clientkey = aging.clientkey )
AND ( pmtchecks.debtorkey = aging.debtorkey )
WHERE ( pmtchecks.debtorkey = 36927 )
AND ( transactions.status = 0 )
AND ( transactions.postdate <= '31-May-2012' )
AND ( ( transactions.postdate >= '01-May-2012' )
OR ( clients.clientno = 'UNKNOWN' ) )
ORDER BY pmtchecks.checkdate,
pmtchecks.checkno
Hi this is kind of dummy code i cnt say its exactly right but the idea will be exactly same to get the result
var anonymousType= (from pm in pmtchecks
join tr in transactions
on pm.transkey equals tr.transkey //INNERJOIN
join cl in clients
on tr.clientKey equals cl.clientKey
join ag in aging
on pm.debtorkey equals ag.debtorKey into ljoin //Left Join
from lj in ljoin.DefaultOrEmpty()
where pm.debortkey==36927 && tr.status==0 && tr.postdate<="31-May-2012" && tr.postdate>="01-May-2012" //u will have to change this to date format first
Select new {PostDate=tr.postdate, TransClientKey=tr.clientkey,TransType=tr.type,ClientNo=cl.clientno,CliNoStmt=cl.nomst ?? 0,AgeNoStmt=ag.nomst ??0,Pmtchecks=pm } //Anonymous type from this you can extract the values and fill to your custom type
).OrderBy(o=>o.Pmtchecks.checkdate).OrderBy(o=>o.Pmtchecks.checkno).ToList();
Hope this will help.
LINQ Query Samples
EDITED
var pmtchecks = from p in urcontext.pmtchecks
join t in urcontext.transactions on p.transkey equals t.transkey
join a in urcontext.aging on t.clientkey equals a.clientkey into details
from d in details.Where( a => ( a.debtorkey == p.debtorkey)).DefaultIfEmpty()
where (p.debtorkey == 36927 && t.status == 0 && t.postdate <= '31-May-2012'
&& (t.postdate >= '01-May-2012' || c.clientno == 'UNKNOWN' ))
orderby p.checkdate, p.checkno
select new
{
t.postdate,
t.clientkey,
// TransClientKey = t.clientkey, //only works if TransClientKey is property
t.type ,
//TransTypet = t.type ,//property
c.clientno,
c.nostmt,
//CliNoStmt = c.nostmt ?? 0,//property
a.nostmt//,
//AgeNoStmt = nostmt ?? 0,//property
//p. ... //follow above for p columns
};
I am trying to convert this expression into LINQ from SQL, but a bit too difficult for me, maybe you can help me with this!
SELECT TOP (2) RecipeID, UserID, Name, Servings, PreparationTime, TotalTime, DifficultyLevelID, CuisineID, DishID, MainIngredientID, PriceLevelID, FlavourID, Instructions,
Notes, Thumbnail, VideoLink
FROM dbo.Recipes
WHERE (RecipeID NOT IN
(SELECT DISTINCT Recipes_1.RecipeID
FROM dbo.Allergies INNER JOIN
dbo.UsersAllergies ON dbo.Allergies.AllergyID = dbo.UsersAllergies.AllergyID INNER JOIN
dbo.IngredientsAllergies ON dbo.Allergies.AllergyID = dbo.IngredientsAllergies.AllergyID INNER JOIN
dbo.Ingredients ON dbo.IngredientsAllergies.IngredientID = dbo.Ingredients.IngredientID INNER JOIN
dbo.RecipesIngredients ON dbo.Ingredients.IngredientID = dbo.RecipesIngredients.IngredientID INNER JOIN
dbo.Recipes AS Recipes_1 ON dbo.RecipesIngredients.RecipeID = Recipes_1.RecipeID INNER JOIN
dbo.Users ON dbo.UsersAllergies.UserID = dbo.Users.UserID INNER JOIN
dbo.AllergyFactors ON dbo.IngredientsAllergies.AllergyFactorID = dbo.AllergyFactors.AllergyFactorID
WHERE (dbo.Users.UserID = 3) AND (dbo.AllergyFactors.AllergyFactorID < 3)))
It would be easier to help you if you showed us what you have already tried, but a Linq expression like this should give you the same result set
var query = (from rec in context.Recipes
where !(from al in context.Allergies
from ua in context.UsersAllergies.Where(x => al.AllergyID == x.AllergyID)
from ia in context.IngredientsAllergies.Where(x => al.AllergyID == x.AllergyID)
from in in context.Ingredients.Where(x => ia.IngredientID == x.IngredientID)
from ri in context.RecipesIngredients.Where(x => in.IngredientID == x.IngredientID)
from re in context.Recipes.Where(x => ri.RecipeID == x.RecipeID)
from us in context.Users.Where(x => ua.UserID == x.UserID)
from af in context.AllergyFactors.Where(x => ia.AllergyFactorID == x.AllergyFactorID)
where us.UserID == 3 && af.AllergyFactorID < 3
select re.RecipeID)
.Distinct()
.Contains(rec.RecipeID)
select new
{
rec.RecipeID,
rec.UserID,
rec.Name,
rec.Servings,
rec.PreparationTime,
rec.TotalTime,
rec.DifficultyLevelID,
rec.CuisineID,
rec.DishID,
rec.MainIngredientID,
rec.PriceLevelID,
rec.FlavourID,
rec.Instructions,
rec.Notes,
rec.Thumbnail,
rec.VideoLink
}).Take(2);