checking if user exists...

[lidds]

I am very new to asp and was wondering the best way to check if a user already exists. Obviously this would envolve a select query

 

"select * from regdetails where username='simon'"

 

and then to check to see if any items are within the recordset, but I am unsure how to write the code to do so, can anyone post an example of code???

 

Cheers

 

Simon

[Mister E]

Depending on your DBMS, you could do:

select * from 
regdetails 
where LOWER(username)=LOWER(@username) AND password=@password

 

And then, assuming you have a DataSet "ds":

bool valid = (ds.Tables[0].Rows.Count > 0);

 

Note: make sure to test case sensitivity on the SQL query for your particular DBMS. The above would work for SQL Server.

[HJB417]

GenericDbCommand cmd;
cmd.CommandText = "select count(*) from regdetails where username=@username";
cmd.Parameters.Add("@username", "simon");
bool exists = Convert.ToBoolean(cmd.ExecuteScalar());

please choose the appropriate sql for the right job.

treat the data returned by the sql server like the items you take on a hiking trip (you only take what you need)

In this case, you dont need all of the data of all of the columns for 1 records in the 'regdetails' table. Use count() instead.