need to search mysql for something and return the value in the next colum

Question

Hi all, 

i have a very simple table in mysql, i can connect etc fine, and i think i have the query i need, but how do i get this working in c#?

what it will basically do is find a username based on the windows username.

sUserName = Environment.UserName;

"'select sms_un from smsusers where domain_un = ' + sUserName;";

sorry its quite hard to describe :) does this make sense?

Answer 1

I Had Changed Update statement as u said "Update Customer Set Name='@name,Address='@address'. but it is showing an OleDbException "The changes you requested to the table were not successful because they would create duplicate values in the index, primary key, or relationship. Change the data in the field or fields that contain duplicate data, remove the index, or redefine the index to permit duplicate entries and try again. " The Update statement that i had written is correct only but, i think some other statement should write to update all the records at a time..i am in search of that only...Any Way ThanQ for Your Suggestion

Answer 2

Hey Chaitanya, You have written you update query like this
"update customer set Name1=@name,Address=@address where Name1=@name";"

What this will do is, it will update the name and the address of the customer according to the specific name of the Customer.

For example...
table name: tblCustomer

Columns:
CustID        CustName        CustAddress
01                Shiv                Mumbai
02                Anand                Delhi
03                Chaitanya        Kolkata

Now If I write a query which you have written in the Code....
"update customer set Name1=@name,Address=@address where Name1=@name";

Suppose in the @name parameter i get the value as 'Anand', in the @address parameter i get the value as 'Pune' and again for the @name parameter in the where clause i get the value as 'Anand'.... So logically your query will look something like this...
"Update Customer Set Name1='Anand', Address='Pune' where Name1='Anand';"

It means that you are updating a record where the Name1 is 'Anand', hence it is just recording only one record... If you wanna update all the records, then simply put this Update Query as mentioned below...

" Update Customer Set Name='@name', Address='@address' " what this will do is that it will update all the members with the name and the address value that you have passed in the parameter.....

General knowledge - Usually you should always update a record based on the ID (Primary key) of the table.... it is much safe since it will affect only a specific record.... If you pass a name or an address in the where clause, it will affect all the records which have the same name and the address in the database table..


Please let me know, if this solution is pro[er.... and is possible please explain the functionality if the answered post is incorrect....

Thank you!!!