Lose row data while using SqlDataReader.ReadAsync() with sql query with output inserted

Question

I have such piece of code and after execution I get N rows in my database table and N-1 rows data are returned from method. Can't understand what I'm doing wrong and find any examples of similar problem. Does I lose data because of sql query, or I did a mistake in a code? Please, help.

    private String sqlCommandSample = "insert into [dbo].[SomeTable] " +
                         "(Title, Descript) " +
                         "output inserted.Title " +
                         "select Item.value('title[1]', 'nvarchar(max)'), Item.value('description[1]', 'nvarchar(max)') " +
                         "from @Xml.nodes('nodes/node') as Result(Item) " +
                         "where not exists (select * from [dbo].[SomeTable] " +
                         "where ([Title] = Item.value('Title[1]', 'nvarchar(200)')))";

    public async Task<List<String>> FillTableAsync(String sqlCommandString, GetArticleLink getArticleLink)
    {
        using (var sqlConnection = new SqlConnection(ConnectionString))
        {
            await sqlConnection.OpenAsync();

            using (var sqlCommand = new SqlCommand(sqlCommandString, sqlConnection))
            {
                using (var sqlReader = await sqlCommand.ExecuteReaderAsync())
                {
                    var listOfLinks = new List<String>();

                    if (await sqlReader.ReadAsync())
                    {
                        while (await sqlReader.ReadAsync())
                        {
                            listOfLinks.Add(await GetLink(sqlReader));
                        }
                    }
                    return listOfLinks;
                }
            }
        }
    }

    private async Task<String> GetLink(DbDataReader reader)
    {
        return await reader.GetFieldValueAsync<String>(0);
    }

Remus Rusanu · Accepted Answer · 2013-09-14 11:26:42Z

4

 if (await sqlReader.ReadAsync())
 {
     while (await sqlReader.ReadAsync())
     ...

Here you just lost a row. while is enough, no need for if.

answered Sep 14, 2013 at 11:26

Remus Rusanu

296k42 gold badges459 silver badges583 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Dimentii.Dy Over a year ago

You're right! Thank you very much! Need to be more accurate next time.

Rachel Over a year ago

You can use the HasRows property to check if there are rows

Collectives™ on Stack Overflow

Lose row data while using SqlDataReader.ReadAsync() with sql query with output inserted

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related