static async Task InsertBug01(ApplicationDbContext dbContext)
{
//https://github.com/aspnet/EntityFrameworkCore/issues/18263#issuecomment-541369431
var key = new CdKey
{
//Id = Guid.NewGuid().ToString(), //this bug fix solution
Name = "asp.net",
BuildType = BuildType.Test
};
await dbContext.AddAsync(key);
}
static async Task FixChange02(ApplicationDbContext dbContext)
{
/*
* I don't think this lazy loading is bad, instead I think it's very cool.
* I hope the official can have some documentation about this, or help other through my example.
*/
var firstkey = new CdKey
{
Id = Guid.NewGuid().ToString(), //this bug fix solution
Name = "asp.net",
BuildType = BuildType.Test
};
await dbContext.CdKeys.AddAsync(firstkey);
await dbContext.SaveChangesAsync();
var keys = dbContext.CdKeys?.Where(k => k.BuildType == BuildType.Test)?.ToList();//Because the loading is done
foreach (var item in keys)
{
var values = dbContext.keyValues.Where(v => v.KeyId == item.Id).ToList();//So,No error
}
}
static async Task Change02(ApplicationDbContext dbContext)
{
//https://github.com/aspnet/EntityFrameworkCore/issues/18358
//fix this, using SqlServer then enable MARS support.
//https://docs.microsoft.com/en-us/sql/relational-databases/native-client/features/using-multiple-active-result-sets-mars?view=sql-server-ver15
var firstkey = new CdKey
{
Id = Guid.NewGuid().ToString(), //this bug fix solution
Name = "asp.net",
BuildType = BuildType.Test
};
await dbContext.CdKeys.AddAsync(firstkey);
await dbContext.SaveChangesAsync();
var keys = dbContext.CdKeys?.Where(k => k.BuildType == BuildType.Test);
foreach (var item in keys)
{
var values = dbContext.keyValues.Where(v => v.KeyId == item.Id).ToList();//InvalidOperationException:
//There is already an open DataReader associated with this Command which must be closed first.
}
}
