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Entity framework and Exists clause


Entity framework and Exists clause

By : user3851541
Date : October 16 2020, 11:12 AM
Any of those help I'm a rookies of EF so, sorry for my perhaps foolish question. , EXISTS in SQL ~= Any in LINQ:
code :


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General persist method in Entity Framework - inserting or updating (if exists) entity

General persist method in Entity Framework - inserting or updating (if exists) entity


By : alo malo
Date : March 29 2020, 07:55 AM
I think the issue was by ths following , In your example where you can't recognize if a Company instance is new or has been formerly loaded from the database you must query the DB:
code :
public void Persist(Company company)
{
    var companyInDb = _dbSet.SingleOrDefault(c => c.Id == company.Id);
    if (companyInDb != null)
    {
        _context.Entry(companyInDb).CurrentValues.SetValues(company);
    }
    else
    {
        _dbSet.Add(company);
    }
    _context.SaveChanges();
}
public class Company
{
    public Company()
    {
    }

    public Company(bool isNew)
    {
        Id = Guid.NewGuid();
        _isNew = isNew;
    }

    public Guid Id { get; set; }
    public string Name { get; set; }

    private bool _isNew;
    public IsNew { get { return _isNew; } }
}
public void Persist(Company company)
{
    if (!company.IsNew)
    {
        _context.Entry(company).State = EntityState.Modified;
    }
    else
    {
        _dbSet.Add(company);
    }
    _context.SaveChanges();
}
Entity Framework - Use Join clause on an entity collection

Entity Framework - Use Join clause on an entity collection


By : jeremyc
Date : March 29 2020, 07:55 AM
around this issue I'm a beginner beginner with entity framework and I need your help to build a query.
code :
var result = context.table1.Where(x => x.table2.Any(y => y.idTable3 == 4)).ToList();
Entity Framework 6 related entity where datetime clause doesn't translate to SQL

Entity Framework 6 related entity where datetime clause doesn't translate to SQL


By : Nuwan Guyes
Date : March 29 2020, 07:55 AM
Is exists level 2 cache for Entity Framework 6+ not updating whole entity?

Is exists level 2 cache for Entity Framework 6+ not updating whole entity?


By : user1673712
Date : March 29 2020, 07:55 AM
will be helpful for those in need Disclaimer: I'm the owner of the project Entity Framework Plus
Our Query Cache http://entityframework-plus.net/query-cache doesn't invalidate or update the whole entity.
Unable to Apply Linq Where Clause to Linked Entity in Entity Framework Core

Unable to Apply Linq Where Clause to Linked Entity in Entity Framework Core


By : user2511930
Date : March 29 2020, 07:55 AM
like below fixes the issue I have a EventEntity which has IEnumerable PocEntity. , The problem is with the first where condition:
code :
.Where(x => x.Poc.Where(p => p.PocId.Equals(pocId)));
.Where(x => x.Poc.Where(p => p.PocId.Equals(pocId)).Any())
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