How to catch check constraint violation error in Database.

In previous pose I have discussed how to catch error occurred by Store procedure. Now I am going to show you how to catch CHECK constraint error in ADO.NET code. And surprisingly there is nothing to change in your ADO.NET code. Smart try-catch mechanism of C# is enough to handle the situation.

Now I will create one table with one check constraint like,

create table TestTable(id int not null primary key identity(1,1),sal int not null CHECK(sal >0))

Here you can see my sal column will not take any negative value as I have set one check constraint in this column.

Now this is our ADO.NET code , When I will try to fire

insert into TestTable(sal) values(-100)

query to this table, It will throw error.

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Collections;

using System.Data;

using System.Diagnostics;

using System.Data.SqlClient;

namespace BlogProject

{

    class Program

    {

        static void Main(string[] args)

        {

            SqlConnection con = new SqlConnection();

            con.ConnectionString = "Data Source=SERVERNAME;Initial Catalog=test;Integrated Security=True";

            con.Open();

            SqlCommand cmd = new SqlCommand();

            cmd.CommandText = "insert into TestTable(sal) values(-100)";

            cmd.CommandType = CommandType.Text;

            cmd.Connection = con;

           

            try

            {

                int Value = (Int32)cmd.ExecuteNonQuery();

            }

            catch (SqlException ex)

            {

                Console.Write("Error Occur in Database" +"\n" +"Error Code"+  ex.Number +"\n" + "Error Message" + ex.Message);

            }

            Console.ReadLine();

        }

    }

}