Please help - new to Ruby - stumped (sql and array returns)

I am new to the language and trying to add a couple of simple tests on
user input, followed by a DB query, then using the returned values
(where the problem lies)

I first run a find_by_sql similar to this

@my_names = modelname.find_by_sql

I then check to see if NO returns via

if @my_names.size == 0


My question is, how do I access the values that are now in the array. I
seem to be able to set session variables by way of

session[:whatever] = @my_names[0].column_name

but am unable to perform a if construct that looks like

if @my_names[0].column_name == “TEST VALUE”

I keep getting an undefined method error when I try to run the code.
Thanks very much in advance for any assistance with this.

I have moved this to the Rails forum.