Unable to convert SQL query to linq which has join, group by and where conditions

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I am unable to convert sql query to lamba expression in entity framework core. below is the sql query -

select c.company_id,industry_id,company_name,city,count(first_name) "Count" from company c join employee e on c.Company_id = e.Company_id where c.Company_name in ('"15 Minutes" Inc.', '!mpactMEDIA','"Stuffed" Cajun Meat Market & Specialty Food Store' ) group by c.company_id,industry_id,Company_name,city

I need to select only few columns from both tables.
please help me on writing an lamba expression.

What I have tried:

I tried as below mentioned code its not working

_entities.Company.Join(_entities.Employee,
                            com => com.Company_id,
                            emp => emp.Company_id,
                            (com, emp) => new SearchCompany
                            {
                             companyID = com.Company_id,
                             industryType = com.industry_id,
                             company = com.Company_name,
                             location = com.City,
                             contacts = emp.First_name.Count()
                            })
                           .Where(input => input.company == sb.ToString())
      .GroupBy(c => new { c.companyID, c.industryType, c.company, c.location });

I am having entity(Search) which has companyID,industryType,company,location,contacts as members of entity. I am return the value of the linq query to IQuerayable<search>. I am getting error as cannot convert to IQuerayable<search> from IQueryable<Igrouping< anonymous>>>

Posted 11-Jul-18 22:20pm

sri4dotnet

Updated 6-Feb-19 22:46pm

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Maciej Los · Answer 1 · 2019-02-06T22:46:00

I'd do that this way:

C#

string[] companies = {"'15 Minutes' Inc.", "!mpactMEDIA", "'Stuffed' Cajun Meat Market & Specialty Food Store"};
var result = _entities.Company
    .Where(com=>companies.Contains(com.Company_name))
    .Select(com=> new SearchCompany
    {
        companyID = com.Company_id,
        industryType = com.industry_id,
        company = com.Company_name,
        location = com.City,
        contacts = _entities.Employee.Where(e=>e.Company_id==com.Company_id).Count()
    });

[EDIT]Thanks to Richard Deeming[^] for valuable suggestion of code improvement.[/EDIT]