Connexion to database SQL SERVER (2019)

Question

Hi,
I've an Blazor Wasm application.
Until now I worked with a local database that I've created by migration.

"Data Source=(LocalDB)\\MSSQLLocalDB;AttachDbFilename=C:\\Users\\...\\source\\repos\\DATASERVEUR\\Developers.mdf;Integrated Security=True;Connect Timeout=30"

With this connection all things is ok

Now I want to connect my application with the data base in sql server (2019)

Data Source=servername;Initial Catalog=Developers;Integrated Security=True;

the table dbo.Developers was created by import of the flat file (csv)

When I run my application I've a message :

InvalidCastException: Unable to cast object of type 'System.Byte' to type 'System.Int32'.

The get action where I've this message :

  [HttpGet]
        public async Task<IActionResult> Get()
        {           
            var devs = await _context.Developers.ToListAsync();
            return Ok(devs);
        }

Have you an idea how I can solve this problem?
thanks in advance

Answer 1

the column mapping in the dbcontext is wrong, or when you ported to Sqlserver you made the column types different. for us to fix, we would need the sql server table definition, and the table definition in the dbcontext.

Answer 2

I have a vague recollection I ran into this problem when one of the columns was using either tinyint or smallint type in the database and the model was using byte. I forgot the resolution, unfortunately.

Answer 3

What happens if you remove this for now
[DatabaseGenerated(DatabaseGeneratedOption.Computed)]
public int Calcul
{
get
{
if (DateSoldePr.Year < 2000)
{
return 0;
}
if (DateSoldePr.Year > 2000)
{
return (int)Math.Floor((DateTime.Today - DateSoldePr).TotalDays);
}
else
{
return 0;
}
}
}

? Could it be due to nullability in that column?

Answer 4

I think I have to follow up recommendation @AgaveJoe .
1-make the migration , it's ok
2- Import the data from flat File (CSV)

I try to do it in sql but I 've a message
Have you an idea how I can solve this problem?

Answer 5

Table definition in the dbcontext.

  // [NotMapped]
    public partial class Developer
    {

        public int Id { get; set; }
     //   [Required]
    //    [StringLength(6)]
       // [Display(Name = "Numéro ECR")]
        public string ECR { get; set; }
        public DateTime DateCrea { get; set; }
        public string Atelier { get; set; }
        public string Nom { get; set; }
        public string PNC { get; set; }
        public string DesignationC { get; set; }
        public string AmdtC { get; set; }
        public string IndiceC { get; set; }
        public string PNP { get; set; }
        public string Produit { get; set; }
        public string AmdtP { get; set; }
        public string IndiceP { get; set; }
        public DateTime DateP { get; set; }
       // [Required]
        public string Description { get; set; }
        public string Analyse { get; set; }
        public string BlocT { get; set; }
        public string BlocM { get; set; }
        public string FEE { get; set; }
        public string Statut { get; set; }
        public string CodePrio { get; set; }
        public DateTime DateSoldePr { get; set; }
        public DateTime DateSuivi { get; set; }
        [DatabaseGenerated(DatabaseGeneratedOption.Computed)]
        public int Calcul
        {
            get
            {
                if (DateSoldePr.Year < 2000)
                {
                    return 0;
                }
                if (DateSoldePr.Year > 2000)
                {
                    return (int)Math.Floor((DateTime.Today - DateSoldePr).TotalDays);
                }
                else
                {
                    return 0;
                }
            }
        }
        public int RAF { get; set; }
        public string CommentairePrio { get; set; }
        public string DTbem { get; set; }
        public string DTbee { get; set; }
        public string DTrd { get; set; }
        public string DImi { get; set; }
        public string BlSAQ { get; set; }
        public string ECO { get; set; }
        public DateTime DateSolde { get; set; }
        public string Commentaires { get; set; }

    }

sql server table definition

CREATE TABLE [dbo].[Developers](
 [Id] [int] NOT NULL,
 [ECR] [nvarchar](6) NOT NULL,
 [DateCrea] [datetime] NOT NULL,
 [Atelier] [nvarchar](50) NOT NULL,
 [Nom] [nvarchar](50) NOT NULL,
 [PNC] [nvarchar](50) NOT NULL,
 [DesignationC] [nvarchar](50) NOT NULL,
 [AmdtC] [nvarchar](50) NOT NULL,
 [IndiceC] [nvarchar](50) NOT NULL,
 [PNP] [nvarchar](50) NULL,
 [Produit] [nvarchar](50) NOT NULL,
 [AmdtP] [nvarchar](50) NOT NULL,
 [IndiceP] [nvarchar](50) NOT NULL,
 [DateP] [datetime] NOT NULL,
 [Description] [nvarchar](max) NOT NULL,
 [Analyse] [nvarchar](max) NOT NULL,
 [BlocT] [int] NOT NULL,
 [BlocM] [int] NOT NULL,
 [FEE] [nvarchar](1) NULL,
 [Statut] [nvarchar](10) NULL,
 [CodePrio] [nvarchar](10) NULL,
 [DateSoldePr] [datetime] NULL,
 [DateSuivi] [datetime] NULL,
 [RAF] [int] NULL,
 [CommentairePrio] [nvarchar](max) NULL,
 [DTbem] [nvarchar](10) NULL,
 [Dtbee] [nvarchar](10) NULL,
 [DTrd] [nvarchar](10) NULL,
 [DImi] [nvarchar](10) NULL,
 [BlSAQ] [nvarchar](10) NULL,
 [ECO] [nvarchar](10) NULL,
 [DateSolde] [datetime] NULL,
 [Commentaires] [nvarchar](max) NULL
) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY]
GO