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Converted my SQL to LINQ and I am getting System.InvalidOperationException: Client side GroupBy is not supported error

I am getting Unhandled exception. System.InvalidOperationException: Client side GroupBy is not supported when I try to run this LINQ Query in my C# application using EntityFrameworkCore.
This is my LINQ Query.
var test =
(from lbls1 in ctxt.Labels
join att in ctxt.Attributes
on lbls1.Id equals att.LabelId
join img in ctxt.Images
on lbls1.ImageId equals img.Id
where att.plate_region_conf >= min_region_conf
&& att.plate_code_conf >= min_code_conf
&& states.Contains(att.plate_state)
&& cameraid.Contains(img.CameraId)
&& !exclude_filename.Contains(img.Filename)
group lbls1 by new {
att.plate_code,
att.plate_state
} into lbls1
select lbls1).ToList()
This is the original SQL query I created and ran.
Select ImageId FROM Labels as l JOIN Attributes as a ON
a.LabelID = l.Id
JOIN Images as I
On l.ImageId = I.Id
Where
plate_state = states
AND plate_region_conf >= region_conf
AND plate_code_conf >= code_conf
AND plate_stacked = stacked
AND is_edge = edge
AND I.CameraId = cameraid
AND I.Filename <> filename
Group By plate_code, plate_state;
What I read, Client-side evaluation was removed from LINQ but this should still work if this code translate to SQL. I am running MySQL and I did removed ONLY_FULL_GROUP_BY so it should work.Any advice would be appreciated!

You have used SelectMany, which introduce rows duplication. Instead of that you have to use Any function in predicate and navigation property, I hope you have them.
var query =
from label in ctxt.Labels
where
label.Attributes.Any(att =>
att.plate_region_conf >= min_region_conf
&& att.plate_code_conf >= min_code_conf
&& states.Contains(att.plate_state)
)
&& cameraid.Contains(label.Image.CameraId)
&& !exclude_filename.Contains(label.Image.Filename)
select label;
If Label to Image is One to Many relation, you also has to use Any.

SQL Query to Linq to Entities - C#

I have been trying to convert this SQL statement into a linq as i am trying to move the functionality into a program.
Here is the SQL statement
SELECT cust.sg_group_name AS customer,
(SELECT Sum(du.used_space)
FROM sg_groups AS clnt
LEFT JOIN client_disk_usage AS du
ON clnt.sg_group_id = du.sg_group_id
AND clnt.group_role_id = 3
WHERE clnt.parent_group_id = cust.sg_group_id
AND du.day_of_month = 15
AND du.month_of_year = 05
AND du.used_space_year = 2016) AS disk_usage
FROM sg_groups AS cust
WHERE cust.group_role_id = 2
ORDER BY cust.sg_group_name
Essentially the output is just a list with two columns
customer disk_usage
Customer1 136401537652
Customer2 42208008210
If possible i just want to convert this to a linq statement. I have tried putting the query into LinqPad, but it doesn't seem to want to convert from SQL to Linq (just comes up with a blank white page). I have had a crack at the query myself, but i either get something that doesn't work altogether, or an incorrect number of results.
If anyone has any suggestions that would be great!

disk_usage(Sub Query) is a bit Complicated Part. Converted over here. Try this out
var CoreList = (from clnt in EntityName.sg_groups
join du in EntityName.client_disk_usage
on new { GrpId = clnt.sg_group_id, RoleId = clnt.group_role_id } equals new { GrpId = du.sg_group_id, RoleId = 3 } into LJ
from RT in LJ.DefaultIfEmpty()
where du.day_of_month == 15 && du.month_of_year == 05 && du.used_space_year == 2016
select new {clnt, du, RT}
).ToList();
var CoreListSet = CoreList.Select(i=> new YourEntityClass
{
//Fetch the ParentGroupId & UsedSpace
}).ToList();
var CoreListComplete = (from cl in CoreListSet
join cust in EntityName.sg_groups
on cust.sg_group_id equals cl.parent_group_id).ToList();
Now get the sum of CoreListComplete & just implement the base Select Query in Linq!

Apologies for the delayed response. I've marked #Anil answer up as this is the one that helped me find the answer. You solution did work #Sathish but it can be accomplished in a single command. Here is my final solution. Many thanks for your help!
storeGridUsage = (
from cust in db.sg_groups
from client in db.sg_groups
join du in db.client_disk_usage on client.SG_GROUP_ID equals du.SG_GROUP_ID
where client.GROUP_ROLE_ID == 3
where client.PARENT_GROUP_ID == cust.SG_GROUP_ID && du.DAY_OF_MONTH == day && du.MONTH_OF_YEAR == month && du.USED_SPACE_YEAR == year
where cust.GROUP_ROLE_ID == 2
orderby cust.SG_GROUP_NAME
group new {cust, du} by cust.SG_GROUP_NAME
into g
select new StoreGridUsage
{
CustomerName = g.Key,
DiskUsageInBytes = g.Sum(o => o.du.USED_SPACE)
}).ToList();

Conversion of SQL into LINQ

I need help converting some an SQL select into LINQ
Here is the original SQL:
Select Top 1 IsNull(ct.Template, t.Template) as Template
From Template t
Left Outer Join ClientTemplate ct On t.TemplateTypeId = ct.TemplateTypeId And ct.ClientId = 149
Where t.TemplateTypeId = (Select TemplateTypeId From QuoteType Where QuoteTypeId = 7)
Order By t.Version DESC, ct.Version DESC
I'm using Entity Framework and have entities for QuoteTypes, ClientTemplates and Templates.
The above SQL gets the Template from the ClientTemplate table for client 149 (uses a variable in the real code) for a particular QuoteType. If there is no entry in the CLientTemplate table then it returns the Template from the main Template table for the same QuoteType!
My idea was to query the QuoteType first and then query the ClientTemplate table to see if one exists and if not query the Template table instead. The problem is this will result in three queries but I'm sure it can be done in one swoop!?
Can anyone have a go at writing the LINQ for me?
Here's my mess so far:
QuoteType quoteType = (from qt in this.entities.QuoteTypes where qt.QuoteTypeID == this.SelectedNewQuoteTypeID select qt).First();
if (quoteType != null && quoteType.TemplateTypeID.HasValue)
{
int quoteTypeTemplateTypeID = (int)quoteType.TemplateTypeID;
var query = (from t in this.entities.Templates
join ct in this.entities.ClientTemplates on t.TemplateTypeID equals ct.TemplateTypeID
into a
from b in a.DefaultIfEmpty(new ClientTemplate())
where t.TemplateTypeID == quoteTypeTemplateTypeID
orderby t.Version descending
select new
{
T1 = t.Template1,
T2 = b.Template
}).First();
// Check the query to see if T1 and T2 are null and use whichever one isn't!
// TODO !!!
}
else
{
return string.Empty;
}
I kind of gave up once I got that far and posted this! My example still does two queries and does not select based on the client ID. It also does not have the second order by on the client template table.
I've inherited the original SQL statement so maybe the problem is with that being badly written in the first place!?
Over to you...

I haven't tested it but maybe you could try something like this
from t in this.entities.Template
from ct in this.entities.ClientTemplate.Where(x => t.TemplateTypeId == ct.TemplateTypeId && ct.ClientId == 149).DefaultIfEmpty()
where t.TemplateTypeId == (from x in this.entities.QuoteType where x.QuoteTypeId == 7 select x.TemplateTypeId).FirstOrDefault()
orderby t.Version descending, ct.Version descending
select new { ct.Template == null ? t.Template : ct.Template }

I think this might work, although this is untested, from reading it appears you can't add multiple join conditions to a LinQ statement so you can just specify it in the where clause
So here ya go, I tried to convert the SQL word for word so here's my attempt. If it does everything I think it will do it will work.
int templateTypeId;
templateTypeId= (context.QuoteType.Where(x => x.QuoteTypeId == 7)).FirstOrDefault().TemplateTypeId
var qry =(
from t in context.Template
join ct in context.ClientTemplate on
t.TemplateTypeId equals ct.TemplateTypeId into cts
from ct in cts.DefaultIfEmpty() //left join
where t.TemplateTypeId == templateTypeId
&& ct.ClientId == 149
order by t.Version descending, ct.Version descending
select new
{
Template = (ct.Template != null) ? ct.Template : t.Template //ternary operator
}).FirstOrDefault();

T-SQL to LINQ conversion

I have the following SQL statement
SELECT
c.CorpSystemID, c.SystemName ,
case when a.TaskItemID is NULL then 'false' else 'true' end as Assigned
FROM CorpSystems c
LEFT OUTER JOIN
(SELECT CorpSystemID, TASKItemID
FROM AffectedSystems
where TASKItemID = 1) a ON c.CorpSystemID = a.CorpSystemID
Can anyone please help me to convert this statement to LINQ?
Thank you.

Ok so assume you've got a list of your CorpSystem objects in a variable called Corpsystems and a list of your AffectedSystem objects in a variable called AffectedSystems. Try the following:
Edit: For a join on all Affected Systems, try this:
var matches = from c in CorpSystems
join a in AffectedSystems on c.CorpSystemId equals a.CorpSystemId into ac
from subSystem in ac.DefaultIfEmpty()
select new
{
c.CorpSystemId,
c.SystemName,
Assigned = subSystem != null && subSystem.TaskItemId != null
};
Or for just AffectedSystems that have a TaskItemId of 1:
var matches = from c in CorpSystems
join a in AffectedSystems.Where(as => as.TaskItemId == 1)
on c.CorpSystemId equals a.CorpSystemId into ac
from subSystem in ac.DefaultIfEmpty()
select new
{
c.CorpSystemId,
c.SystemName,
Assigned = subSystem != null && subSystem.TaskItemId != null
};

See the answers to the following SO question SQL to LINQ Tool, assuming that you do not want to go through the process by hand.

How to rewrite a SQL query in LINQ to Entities?

I'm trying to rewrite a SQL query in LINQ to Entities. I'm using LINQPad with a typed datacontext from my own assembly to test things out.
The SQL query I'm trying to rewrite:
SELECT DISTINCT variantID AS setID, option_value AS name, option_value_description AS description, sort_order as sortOrder
FROM all_products_option_names AS lst
WHERE lst.optionID=14 AND lst.productID IN (SELECT productID FROM all_products_option_names
WHERE optionID=7 AND option_value IN (SELECT name FROM brands
WHERE brandID=1))
ORDER BY sortOrder;
The LINQ to Entities query I've come up with so far (which doesn't work due to a timeout error):
from a in all_products_option_names
where a.optionID == 14 && all_products_option_names.Any(x => x.productID == a.productID && x.optionID == 7 && brands.Any(y => y.name == x.option_value && y.brandID == 1))
select new
{
id = a.variantID,
name = a.option_value,
description = a.option_value_description,
sortOrder = a.sort_order,
}
This is the error I get when I run the above query: An error occurred while executing the command definition. See the inner exception for details.
And the inner exception is: Timeout expired. The timeout period elapsed prior to completion of the operation or the server is not responding.
Edit:
I use MySQL and probably that's why LINQPad doesn't show me the generated SQL.
The SQL version doesn't time out.
Edit 2:
I solved the problem by completely changing the query, so this question is irrelevant now.
I marked Steven's response as the correct one, because he was closest to what i was trying to achieve and his response gave me the idea which led me to the solution.

Try this:
var brandNames =
from brand in db.Brands
where brand.ID == 1
select name;
var brandProductNames =
from p in db.all_products_option_names
where p.optionID == 7
where brandNames.Contains(p.option_value)
select p.productId;
var results =
from p in db.all_products_option_names
where p.optionID == 14
where brandProductNames.Contains(p.productId)
select new
{
setID = p.variantID,
name = p.option_value,
description = p.option_value_description,
sortOrder = p.sort_order
};

I would recommend doing joins rather than sub-select's as you have them. Sub-selects are not very efficient when you look at performance, it's like having loops inside of loops when you code , not a good idea. This could actually cause that timeout your getting if your database is running slowly even thou that looks like a simple query.

I would try using joins with a distinct at the end like this:
var results =
(from p in db.all_products_option_names
join p2 in db.all_products_option_names on p.productId equals p2.productId
join b in db.Brands on p2.option_value equals b.name
where p.optionID == 14
where p2.optionID == 7
where b.BrandID == 1
select new
{
setID = p.variantID,
name = p.option_value,
description = p.option_value_description,
sortOrder = p.sort_order
}).Distinct();
Or you could try using joins with the into and with an any like so
var results =
from p in db.all_products_option_names
join p2 in (from p3 in db.all_products_option_names.Where(x => x.optionId == 7)
join b in db.Brands.Where(x => x.BrandID == 1) on p3.option_value equals b.name
select p3) into pg
where p.optionID == 14
where pg.Any()
select new
{
setID = p.variantID,
name = p.option_value,
description = p.option_value_description,
sortOrder = p.sort_order
};