error, string or binary data would be truncated when trying to insert

Question

From @gmmastros's answer

Whenever you see the message....

string or binary data would be truncated

Think to yourself... The field is NOT big enough to hold my data.

Check the table structure for the customers table. I think you'll find that the length of one or more fields is NOT big enough to hold the data you are trying to insert. For example, if the Phone field is a varchar(8) field, and you try to put 11 characters in to it, you will get this error.

I had this issue although data length was shorter than the field length. It turned out that the problem was having another log table (for audit trail), filled by a trigger on the main table, where the column size also had to be changed.

In one of the INSERT statements you are attempting to insert a too long string into a string (varchar or nvarchar) column.

If it's not obvious which INSERT is the offender by a mere look at the script, you could count the <1 row affected> lines that occur before the error message. The obtained number plus one gives you the statement number. In your case it seems to be the second INSERT that produces the error.

Just want to contribute with additional information: I had the same issue and it was because of the field wasn't big enough for the incoming data and this thread helped me to solve it (the top answer clarifies it all).

BUT it is very important to know what are the possible reasons that may cause it.

In my case i was creating the table with a field like this:

Select '' as  Period, * From Transactions Into #NewTable

Therefore the field "Period" had a length of Zero and causing the Insert operations to fail. I changed it to "XXXXXX" that is the length of the incoming data and it now worked properly (because field now had a lentgh of 6).

I hope this help anyone with same issue :)

Some of your data cannot fit into your database column (small). It is not easy to find what is wrong. If you use C# and Linq2Sql, you can list the field which would be truncated:

First create helper class:

public class SqlTruncationExceptionWithDetails : ArgumentOutOfRangeException
{
    public SqlTruncationExceptionWithDetails(System.Data.SqlClient.SqlException inner, DataContext context)
        : base(inner.Message + " " + GetSqlTruncationExceptionWithDetailsString(context))
    {
    }

    /// <summary>
    /// PArt of code from following link
    /// http://stackoverflow.com/questions/3666954/string-or-binary-data-would-be-truncated-linq-exception-cant-find-which-fiel
    /// </summary>
    /// <param name="context"></param>
    /// <returns></returns>
    static string GetSqlTruncationExceptionWithDetailsString(DataContext context)
    {
        StringBuilder sb = new StringBuilder();

        foreach (object update in context.GetChangeSet().Updates)
        {
            FindLongStrings(update, sb);
        }

        foreach (object insert in context.GetChangeSet().Inserts)
        {
            FindLongStrings(insert, sb);
        }
        return sb.ToString();
    }

    public static void FindLongStrings(object testObject, StringBuilder sb)
    {
        foreach (var propInfo in testObject.GetType().GetProperties())
        {
            foreach (System.Data.Linq.Mapping.ColumnAttribute attribute in propInfo.GetCustomAttributes(typeof(System.Data.Linq.Mapping.ColumnAttribute), true))
            {
                if (attribute.DbType.ToLower().Contains("varchar"))
                {
                    string dbType = attribute.DbType.ToLower();
                    int numberStartIndex = dbType.IndexOf("varchar(") + 8;
                    int numberEndIndex = dbType.IndexOf(")", numberStartIndex);
                    string lengthString = dbType.Substring(numberStartIndex, (numberEndIndex - numberStartIndex));
                    int maxLength = 0;
                    int.TryParse(lengthString, out maxLength);

                    string currentValue = (string)propInfo.GetValue(testObject, null);

                    if (!string.IsNullOrEmpty(currentValue) && maxLength != 0 && currentValue.Length > maxLength)
                    {
                        //string is too long
                        sb.AppendLine(testObject.GetType().Name + "." + propInfo.Name + " " + currentValue + " Max: " + maxLength);
                    }

                }
            }
        }
    }
}

Then prepare the wrapper for SubmitChanges:

public static class DataContextExtensions
{
    public static void SubmitChangesWithDetailException(this DataContext dataContext)
    {
        //http://stackoverflow.com/questions/3666954/string-or-binary-data-would-be-truncated-linq-exception-cant-find-which-fiel
        try
        {
            //this can failed on data truncation
            dataContext.SubmitChanges();
        }       
        catch (SqlException sqlException) //when (sqlException.Message == "String or binary data would be truncated.")
        {

            if (sqlException.Message == "String or binary data would be truncated.") //only for EN windows - if you are running different window language, invoke the sqlException.getMessage on thread with EN culture
                throw new SqlTruncationExceptionWithDetails(sqlException, dataContext);
            else
                throw;
        }
    }
}

Prepare global exception handler and log truncation details:

protected void Application_Error(object sender, EventArgs e)
{
    Exception ex = Server.GetLastError();
    string message = ex.Message;
    //TODO - log to file
}

Finally use the code:

Datamodel.SubmitChangesWithDetailException();

Another situation in which you can get this error is the following:

I had the same error and the reason was that in an INSERT statement that received data from an UNION, the order of the columns was different from the original table. If you change the order in #table3 to a, b, c, you will fix the error.

select a, b, c into #table1
from #table0

insert into #table1
    select a, b, c from #table2
    union
    select a, c, b from #table3

on sql server you can use SET ANSI_WARNINGS OFF like this:

        using (SqlConnection conn = new SqlConnection("Data Source=XRAYGOAT\\SQLEXPRESS;Initial Catalog='Healthy Care';Integrated Security=True"))
        {
            conn.Open();

            using (var trans = conn.BeginTransaction())
            {
                try
                {
                    using cmd = new SqlCommand("", conn, trans))
                    { 

                    cmd.CommandText = "SET ANSI_WARNINGS OFF";
                    cmd.ExecuteNonQuery();

                    cmd.CommandText = "YOUR INSERT HERE";
                    cmd.ExecuteNonQuery();

                    cmd.Parameters.Clear();

                    cmd.CommandText = "SET ANSI_WARNINGS ON";
                    cmd.ExecuteNonQuery();

                    trans.Commit();
                    }
                }
                catch (Exception)
                {

                    trans.Rollback();
                }

            }

            conn.Close();

        }