c# - Linq 中的查询性能问题

projectType= internshipNameResponses.FirstOrDefault(y => y.QuestionID == 22).Answer, additionalCriteria = internshipNameResponses.FirstOrDefault(y => y.QuestionID == 27).Answer, tamidStudent = internshipNameResponses.FirstOrDefault(y => y.QuestionID == 28).Answer, studentEmail = internshipNameResponses.FirstOrDefault(y => y.QuestionID == 2134).Answer, jobDesc = internshipNameResponses.Where(y => y.QuestionID == 17).Select(x => x.Answer).ToList(), experience = internshipNameResponses.Where(y => y.QuestionID == 21).Select(x => x.Answer).ToList(), VCF = internshipNameResponses.Where(y => y.QuestionID == 4239).Select(x => x.AnswerCode).ToList(), lang = internshipNameResponses.Where(y => y.QuestionID == 23).Select(x => x.Answer).ToList(), codingLang = internshipNameResponses.Where(y => y.QuestionID == 24).Select(x => x.Answer).ToList(), academic = internshipNameResponses.Where(y => y.QuestionID == 25).Select(x => x.Answer).ToList(), HPD = internshipNameResponses.FirstOrDefault(y => y.QuestionID == 26).Answer,

var result = (from cr in CompanyRepresentatives.Where(x=> companyIds.Contains(x.ID) ) join p in QuestionnaireResponses on cr.ID equals p.RespondentID join q in Responses on p.ID equals q.QuestionnaireResponseID into internshipNameResponses join x in Responses on p.ID equals x.QuestionnaireResponseID into posibleAnswerResponses from internshipNameRes in internshipNameResponses from possibleAnsRes in posibleAnswerResponses where internshipNameRes.QuestionID == 2130 && possibleAnsRes.QuestionID == 29 && p.QuestionnaireID == 2 && cr.Active == true && //Applying the name filter (string.IsNullOrEmpty(companyOrInternshipName) || cr.CompanyName.ToLower().Contains(companyOrInternshipName) || (internshipNameRes != null && internshipNameRes.Answer.ToLower().Contains(companyOrInternshipName))) && //Applying the status filter //Applying the year filter //applying the active filter (includeHidden || !p.IsHidden) orderby cr.CompanyName select new { ID = p.ID, Name = internshipNameRes.Answer, CompanyID = cr.ID, Company = cr.CompanyName, CompanyEmail = cr.Email, CompanyDesc = cr.CompanyDescription, usOfficeCity = cr.USOffice_City, isrOfficeoth = cr.IsraelOffice_City_Other, CompanyRank = cr.Rank, projectType= internshipNameResponses.FirstOrDefault(y => y.QuestionID == 22).Answer, additionalCriteria = internshipNameResponses.FirstOrDefault(y => y.QuestionID == 27).Answer, tamidStudent = internshipNameResponses.FirstOrDefault(y => y.QuestionID == 28).Answer, studentEmail = internshipNameResponses.FirstOrDefault(y => y.QuestionID == 2134).Answer, AvailablePositions = possibleAnsRes.Answer, FilledPositions = p.FilledVacancies, Status = p.Status, Visible = !p.IsHidden, DatePosted = p.Created, Rejected = p.IsInternshipRejected, jobDesc = internshipNameResponses.Where(y => y.QuestionID == 17).Select(x => x.Answer).ToList(), experience = internshipNameResponses.Where(y => y.QuestionID == 21).Select(x => x.Answer).ToList(), VCF = internshipNameResponses.Where(y => y.QuestionID == 4239).Select(x => x.AnswerCode).ToList(), lang = internshipNameResponses.Where(y => y.QuestionID == 23).Select(x => x.Answer).ToList(), codingLang = internshipNameResponses.Where(y => y.QuestionID == 24).Select(x => x.Answer).ToList(), academic = internshipNameResponses.Where(y => y.QuestionID == 25).Select(x => x.Answer).ToList(), HPD = internshipNameResponses.FirstOrDefault(y => y.QuestionID == 26).Answer, industry = cr.CompanyIndustry, companySize = cr.CompanySize, usOffice = cr.USOffice_City, isrOffice = cr.IsraelOffice_City, companyType = cr.CompanyType, market = cr.CompanyTargetMarket, financingStage = cr.FinancingStage }).ToList();

var questionIDs = new []{17, 21, 22, 23, 24, 25, 26, 27, 28, 2134, 4239}; var filteredResponses = internshipNameResponses.Where(y => questionIDs.Contains(y.QuestionID)).ToList(); projectType = filteredResponses.FirstOrDefault(y => y.QuestionID == 22).Answer; additionalCriteria = filteredResponses.FirstOrDefault(y => y.QuestionID == 27).Answer; tamidStudent = filteredResponses.FirstOrDefault(y => y.QuestionID == 28).Answer; studentEmail = filteredResponses.FirstOrDefault(y => y.QuestionID == 2134).Answer; jobDesc = filteredResponses.Where(y => y.QuestionID == 17).Select(x => x.Answer).ToList(); experience = filteredResponses.Where(y => y.QuestionID == 21).Select(x => x.Answer).ToList(); VCF = filteredResponses.Where(y => y.QuestionID == 4239).Select(x => x.AnswerCode).ToList(); lang = filteredResponses.Where(y => y.QuestionID == 23).Select(x => x.Answer).ToList(); codingLang = filteredResponses.Where(y => y.QuestionID == 24).Select(x => x.Answer).ToList(); academic = filteredResponses.Where(y => y.QuestionID == 25).Select(x => x.Answer).ToList(); HPD = filteredResponses.FirstOrDefault(y => y.QuestionID == 26).Answer;