MySQL / C# Question

David Chen

Hi All, I have a problem

I have a MySQL Table, one of the columns' Data Type is TinyInt(1)

When I use this line of code it gives an error

int newNumber = int.Parse(string.Format("{0}", reader["someField"]));

I think the reader is reading a bool value

however MySQL Table has row values of 0 & 1 & 6 & 7

so it is not bool true/false type

How can I actually grab that value to store into "int newNumber"

Thanks

9 Replies

Know the answer? Post it — somebody with the same question will find it here.

David Chen15y ago
string sql = "SELECT (newNumber+0) AS abcd FROM tblSomeTable WHERE id = '29954' LIMIT 1";

int newNumber = Convert.ToInt32(reader["abcd"]);

Console.WriteLine(newNumber);

print out 6

problem has to do with the select statement by adding " (newNumber+0)" then everything is ok
Sam Hobbs15y ago
That article was written by someone that is stumbling around but is not an expert. The smart thing to do is to be methodical and find out for sure what is happening instead of guessing. Please do as I said in my last reply.
David Chen15y ago
its TINYINT i think its a mysql.data.dll library error according to this article http://roy.tabulas.com/2008/02/01/@1521896/ do you have any idea? thanks
Sam Hobbs15y ago
Try the following. This should tell you for sure what type the data is. You need to do this for just one record but it won't be a problem if you do it for all records; the results will be the same for all records.

reader.GetDataTypeName(reader.GetOrdinal("someField"))
David Chen15y ago
if i do

bool newNumber = (bool)reader["newField"]

newNumber returns false or true

thats because in that column I have 0, 1, 4, 6 ,7
David Chen15y ago
int newNumber = (int)(byte)reader["fieldName"]; gives me specific cast is not valid
Sam Hobbs15y ago
My guess is that it would be a "Byte" in C#. So try that; try casting reader["someField"] to a Byte.
David Chen15y ago
TinyInt(1) someField not null
Sam Hobbs15y ago
Please don't post the same question more than once at the same time. I am not sure which one to reply to and other people that might help will be unhappy if someone answers your question in a different thread and then they spend time trying to help when you no longer need help.

You should determeine for sure what ype of data that reader["someField"] is. How is it defined for MySQL?