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This function can only be invoked from LINQ to Entities. .All()

I have a List property that I am setting like so:
testCard.LstSummaries =
db.Summaries.Where(
x =>
(x.AID == aId || x.AInformation.RegNumber == aRegNumber) && DbFunctions.TruncateTime(x.Day) == DateTime.Today.Date &&
x.deleted == false).ToList();
Then I have a conditional statement:
if (testCard.LstSummaries.Count > 0)
{
if (
testCard.LstSummaries.All(
x =>
(x.AID == aId || // ERROR HAPPENS ON THIS LINE
x.AInformation.RegNumber == aRegNumber) &&
DbFunctions.TruncateTime(x.Day) == DateTime.Today.Date && x.deleted == false))
{
// .... do something
}
I get an error:
This function can only be invoked from LINQ to Entities.
I want to avoid to make multiple calls to the database.. furthermore testCard.LstSummaries already has the values I am looking for.. but if I do this:
if (testCard.LstSummaries.Count > 0)
{
if (
db.Summaries.All(
x =>
(x.AID == aId || // NO ERROR
x.AInformation.RegNumber == aRegNumber) &&
DbFunctions.TruncateTime(x.Day) == DateTime.Today.Date && x.deleted == false))
{
// .... do something
}
I feel like making this call to the database is pointless because I would be retrieving the same results that are already stored in testCard.LstSummaries, but I can't invoke .All() because it's not LINQ to Entities.
Is there a workaround for this?

Problem is with DbFunctions.TruncateTime(x.Day), because it is converted to sql on runtime. Try to check without it.

LINQ equivalent of SQL NOT IN statement

I have a query that in T-SQL it is
SELECT *
FROM rpm_scrty_rpm_usr ru
WHERE ru.inact_ind = 'N'
AND email_id IS NOT NULL
AND wwid IS NULL
AND LTRIM(RTRIM (email_id)) <> ''
AND dflt_ste_id NOT IN (25,346,350,352,353,354,355,357,358,366,372,411)
When I have been converting it to LINQ, I have everything except the "NOT IN"
var querynonSystem = (from ru in Rpm_scrty_rpm_usrs
where ru.Inact_ind == "N" && ru.Email_id != null && ru.Wwid == null && ru.Email_id.Trim() != ""
&& ru.Dflt_ste_id != 25
select ru).Count();
I did temporarily put in this line && ru.Dflt_ste_id != 25
However I need to have AND dflt_ste_id NOT IN (25,346,350,352,353,354,355,357,358,366,372,411)
I am seeing a lot of different code like
this lambda where !(list2.Any(item2 => item2.Email == item1.Email))
Then var otherObjects = context.ItemList.Where(x => !itemIds.Contains(x.Id));
For my linq query, how can I do this Not In in simple manner?

You can use Contains with !. In addition, if you just want to count rows, you can use Count.
var ids = new List<int> {25, 346, 350, 352, 353, 354, 355, 357, 358, 366, 372, 411};
var querynonSystem = XXXcontext.Rpm_scrty_rpm_usrs.Count(x =>
x.Inact_ind == "N" &&
x.Email_id != null &&
x.Wwid == null &&
x.Email_id.Trim() != "" &&
!ids.Contains(x.Dflt_ste_id));
From comment: if you want to retrieve all, you can still use Where and Select.
var querynonSystem = XXXcontext.Rpm_scrty_rpm_usrs.Where(x =>
x.Inact_ind == "N" &&
x.Email_id != null &&
x.Wwid == null &&
x.Email_id.Trim() != "" &&
!ids.Contains(x.Dflt_ste_id)).Select(x => x).ToList();
FYI: you cannot call Rpm_scrty_rpm_usrs table class to query. Instead, you need DbContext or some other repository.

There is no "not in" operator unless the type of the query is the same as the type you want to filter against (in which case you could use except). Here it is not. You're working on an IEnumerable and you want to filter on it's ID so a list of int. The where with lambda and contains is your best bet and WILL be translated to an in on the SQL side by most providers.
var FilterIds = new List<int>{1,2,3,4,344,3423525};
var querynonSystem = (from ru in Rpm_scrty_rpm_usrs
where ru.Inact_ind == "N" && ru.Email_id != null && ru.Wwid == null && ru.Email_id.Trim() != ""
&& ru.Dflt_ste_id != 25
select ru)
// Use this
.Where(ru=>!FilterIds.Any(id=>ru.dflt_ste_id ==id))
// Or this
.Where(ru=>!FilterIds.Contains(ru.dflt_ste_id))
.Count();

Using Linq to filter by List<ListItem>

I am trying to extend my linq query with additional search criteria to filter the data by sending also a List<Listitem> to the function for processing. The List can contain 1 or more items and the objective is to retreive all items which match any criteria.
Since i am sending several search criteria to the function the goal is to make a more accurate filter result the more information i am sending to the filter. If one or several criterias are empty then the filter will get less accurate results.
Exception is raised every time i execute following code, and I cant figure out how to solve the using statement to include the List<ListItem>. Appreciate all the help in advance!
Exception: Unable to create a constant value of type 'System.Web.UI.WebControls.ListItem'. Only primitive types or enumeration types are supported in this context.
using (var db = new DL.ENTS())
{
List<DL.PRODUCTS> products =
(from a in db.PRODUCTS
where (description == null || description == "" ||
a.DESCRIPTION.Contains(description)) &&
(active == null || active == "" || a.ACTIVE.Equals(active, StringComparison.CurrentCultureIgnoreCase)) &&
(mID == null || mID == "" || a.MEDIA_ID == mID) &&
(mID == null || objTypes.Any(s => s.Value == a.OBJECTS)) //Exception here!
select a).ToList<DL.PRODUCTS>();
return products;
}

Pass collection of primitive values to expression:
using (var db = new DL.ENTS())
{
var values = objTypes.Select(s => s.Value).ToArray();
List<DL.PRODUCTS> products =
(from a in db.PRODUCTS
where (description == null || description == "" || a.DESCRIPTION.Contains(description)) &&
(active == null || active == "" || a.ACTIVE.Equals(active, StringComparison.CurrentCultureIgnoreCase)) &&
(mID == null || mID == "" || a.MEDIA_ID == mID) &&
(mID == null || values.Contains(a.OBJECTS))
select a).ToList<DL.PRODUCTS>();
return products;
}
That will generate SQL IN clause.
Note - you can use lambda syntax to compose query by adding filters based on some conditions:
var products = db.PRODUCTS;
if (!String.IsNullOrEmpty(description))
products = products.Where(p => p.DESCRIPTION.Contains(description));
if (!String.IsNullOrEmpty(active))
products = products.Where(p => p.ACTIVE.Equals(active, StringComparison.CurrentCultureIgnoreCase)));
if (!String.IsNullOrEmpty(mID))
products = products.Where(p => p.MEDIA_ID == mID);
if (mID != null)
products = products.Where(p => values.Contains(p.OBJECTS));
return products.ToList();

Linq isn't able to convert the predicate on ListItem to something useful to Sql.
I would suggest that you pre-project the values of the ListItems into a simple List<string> before using this with Contains (which is converted to IN)
var listValues = objTypes.Select(_ => _.Value).ToList();
List<DL.PRODUCTS> products = ...
listValues.Contains(a.OBJECTS))

Slow Lambda Expression

Can anyone give me any pointers on how to make this run a bit faster?
return mb_entities.prospects.
FirstOrDefault(x => x.address == person.Add &&
x.homePhone == person.HPhone &&
x.bizPhone == person.BPhone &&
x.cellPhone == person.CPhone &&
x.city == person.City &&
x.state == person.State &&
x.zip == person.Zip &&
x.email == person.Email &&
x.firstName == person.FName &&
x.lastName == person.LName &&
x.middleName == person.MName &&
x.genCode == person.GC) ?? new prospect();
Right now it runs in between 160 and 180 Milliseconds. This would be ok if I didn't have to do it 1000 times.
Any tips would be greatly appreciated. Thanks!

Create an index on the most selective columns (for example, on email, zip and lastname). This will speed it up. It should be one index on multiple columns.
You must have a lot of records in your table that it takes 160ms to execute this once. This is unusually long, even when no index is present.

How do you findIndex with conditionals like &&

Let's say you have a List l_mur = new List();
And you populate the list.
Then based on conditions you want to REMOVE some values without requerying...
l_mur.RemoveAt(l_mur.FindIndex(f => (f.xid == tmur.xid && f.sid == tmur.sid && f.mid == tmur.mid && f.bid == tmur.bid)));
However, the code I used here, does not seem to work. It tells me index out of range, but how can it be out of range if I am just searching for something that truly does exist.

List<T>.FindIndex() returns -1 in case there is no match found - which is out of range for List<T>.RemoveAt().
Also note that FindIndex() only returns the index of the first occurrence based on your predicate - if there is more than one match you will only be able to delete the first one of them with your current approach.
A better approach to delete in place based on a predicate would be RemoveAll():
l_mur.RemoveAll(f => (f.xid == tmur.xid && f.sid == tmur.sid && f.mid == tmur.mid && f.bid == tmur.bid));

May be a good idea is to filter the list to a new instance of the list:
var l_mur = l_mur.Where(f => (f.xid != tmur.xid || f.sid != tmur.sid || f.mid != tmur.mid || f.bid != tmur.bid));

Use this code:
l_mur.Remove(l_mur.Find(f => (f.xid == tmur.xid && f.sid == tmur.sid && f.mid == tmur.mid && f.bid == tmur.bid)));