SQL Query zu LINQ-Syntax nicht existieren verwendet und kommen

Question

My SQL-Abfrage wie unten adaequat in SQL ist ich diese Syntax zu LINQ müssen konvertieren

SQL-

SELECT [Key], Id 
FROM LocalizationKeys AS lk 
WHERE NOT EXISTS (SELECT 1 
        FROM Languages AS l 
        JOIN LocalizationValues AS lv ON l.Id = lv.LanguageId 
        WHERE l.Title = 'en-US' AND lv.LocalizationKeyId = lk.Id) 

LINQ-Syntax habe ich versucht,

var result = 

(from lk in localizationKey  
where !(from l in lang 
     join lv in localizationValue on l.Id equals lv.LanguageId 
     where l.Title == "en-US" && lv.LocalizationKeyId == lk.Id select 1).FirstOrDefault() 

select lk).ToList(); 

Erste Fehler:

Operator '!' cannot be applied to operand of type 'int'

Irgendwelche Anhaltspunkte, wo ich Fehler gemacht habe?

Answer 1

Sie mögen dieses versuchen:

(from lk in localizationKey  
where (from l in lang 
     join lv in localizationValue on l.Id equals lv.LanguageId 
     where (l.Title == "en-US" && lv.LocalizationKeyId == lk.Id) 
     select l).FirstOrDefault() == null 
select lk).ToList(); 

oder

(from lk in localizationKey  
where !(from l in lang 
     join lv in localizationValue on l.Id equals lv.LanguageId 
     where !(l.Title == "en-US" && lv.LocalizationKeyId == lk.Id) 
     select l).FirstOrDefault().Any() 
select lk).ToList(); 

Answer 2

Try this:

(from lk in localizationKey  
where (from l in lang 
     join lv in localizationValue on l.Id equals lv.LanguageId 
     where !(l.Title == "en-US" && lv.LocalizationKeyId == lk.Id) select 1).FirstOrDefault() 

select lk).ToList(); 

Answer 3

Ich denke, Ihre ursprüngliche Abfrage ist in Ordnung, die Sie gerade ein anderes Paar hinzufügen müssen Klammern in der Where-Klausel:

(from lk in localizationKey  
    where !((from l in lang 
     join lv in localizationValue on l.Id equals lv.LanguageId 
     where l.Title == "en-US" && lv.LocalizationKeyId == lk.Id select 1).Any()) 
select lk).ToList();