Why is EF core 5.0 inserting duplicate records?

waqar confiz

Why is Entity Framework 5.0 inserting duplicate records in the Database in uncertain behavior when used .AddAsync() method for adding data.

I have checked the existing value from records before inserting but still occurs duplication of value in the Database.

Here is my code.

if (response.Item1.PurchasesItem.Any())
{
    foreach (var rec in response.Item1.PurchasesItem)
    {
        try
        {
            var exist = await _cFCDbContext.PurchaseSaleLog.Where(a => a.IsActive && a.ProductCode == rec.ItemId.Trim() && a.DaxDate.Equals(rec.PurchDate) && !a.IsDeleted).OrderByDescending(a => a.Id).FirstOrDefaultAsync();
            if (exist == null)
            {
                var purchase = new PurchaseSaleLog()
                {
                    ProductCode = rec.ItemId,
                    VendorId = rec.VendorId,
                    Type = ServiceType,
                    PUOM = rec.UOM,
                    Quantity = (rec.PurchQty.Equals("")) ? 0 : Convert.ToInt32(rec.PurchQty),
                    Branch = rec.Branch,
                    BranchStock = (rec.BranchStock.Equals("")) ? 0 : Convert.ToInt32(rec.BranchStock),
                    DaxDate = rec.PurchDate,
                    IsActive = true,
                    IsDeleted = false,
                    CreatedBy = userId,
                    CreatedDate = DateTime.UtcNow,
                    ModifiedBy = userId,
                    ModifiedDate = DateTime.UtcNow
                };
                await _cFCDbContext.PurchaseSaleLog.AddAsync(purchase);
                await _cFCDbContext.SaveChangesAsync().ConfigureAwait(false);
            }
            else
            {
                exist.ProductCode = rec.ItemId;
                exist.VendorId = rec.VendorId;
                exist.Type = ServiceType;
                exist.Quantity = (rec.PurchQty.Equals("")) ? 0 : Convert.ToInt32(rec.PurchQty);
                exist.Branch = rec.Branch;
                exist.PUOM = rec.UOM;
                exist.BranchStock = (rec.BranchStock.Equals("")) ? 0 : Convert.ToInt32(rec.BranchStock);
                exist.DaxDate = rec.PurchDate;
                exist.ModifiedBy = userId;
                exist.ModifiedDate = DateTime.UtcNow;
                _cFCDbContext.PurchaseSaleLog.Update(exist);
                await _cFCDbContext.SaveChangesAsync().ConfigureAwait(false);
            }

        }
        catch (Exception ex)
        {
            continue;
        }
    }
}

2 Replies

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Sachin Singh4y ago
check record exists or not using
var exist = await _cFCDbContext.PurchaseSaleLog.Where(a => a.IsActive && a.ProductCode == rec.ItemId.Trim() && a.DaxDate.Date().Equals(rec.PurchDate.Date()) && !a.IsDeleted).OrderByDescending(a => a.Id).FirstOrDefaultAsync();
However i don't know why are you not using update instead of add. Update also add the data if primary key is not present in the table, Meaning Update() of EF Core is similar to AddOrUpdate() of EF 6.
Yogeshkumar Hadiya4y ago
In condition where you check existig record you check DaxDate with PurchDate. Here it will return true if whole date is match means both date have same date and also same time then it will return true.

You need to check only date.
Pls Refere below example.
using System;

public class Program
{
    public static void Main()
    {

        DateTime dt1=Convert.ToDateTime("07-June-2022 10:00 AM");
        DateTime dt2=Convert.ToDateTime("07-June-2022 11:00 AM");

                // it will return not match because time of both date is different
        if(dt1.Equals(dt2)){
            Console.WriteLine("Match");
        }else{
            Console.WriteLine("Not Match ");
        }


               // it will return match because here we only check date not time
        if(dt1.Date.Equals(dt2.Date)){
            Console.WriteLine("Match");
        }else{
            Console.WriteLine("Not Match ");
        }
    }
}