From: Darin Ginther <darin.ginther@...>
Date: 2008-12-30T05:05:44+09:00
Subject: Creating a class for returing DB results

I'm a ruby noob.  I've managed to accomplish what I want to do in one
long procedural chain of code.  I'm attempting to modularize my code to
prevent duplication, but I'm having trouble with syntax.

What I'm doing:
Manipulating a web page and then doing simple DB validation of the
results.  I do all of this in a ruby script.

What I want to do:
Manipulate web page, then call a validation class, passing that class:
DBName
UserName
UserPassword
return: Single value (numeric).


I'm having trouble with two things:
1) Generic syntax
2) Return value - because Ruby auto returns the value of the last
expression, I have to explicitly return what I'm after, which seems to
drop me out out the class, prior to terminating the DB connection.


What I essentially have currently is:
    dbh= DBI.connect(mydb,dbuser,dbpw)
    sth = dbh.execute("SELECT count(*) FROM #{table} where code =
#{mycode}")
       while row = sth.fetch do
         finalcount=row[0]
         puts finalcount
        end
       sth.finish
    # disconnect from server
        dbh.disconnect if dbh



So, roughly what I'm thinking is:
Class Countdb
   attr_accessor :mydb, :dbuser, :dbpw, :table, :mycode

require 'DBI'

 def initialize(mydb, dbuser, dbpw, table, mycode)
   @mydb = mydb
   @dbuser = dbuser
   @dbpw = dbpw
   @table = table
   @mycode = mycode
 end

 dbh= DBI.connect(mydb,dbuser,dbpw)
    sth = dbh.execute("SELECT count(*) FROM #{table} where code =
#{mycode}")
       while row = sth.fetch do
         finalcount=row[0]      #How do I return this value?
         end
       sth.finish
    # disconnect from server
    dbh.disconnect if dbh
end



I think we can then instantiate this object via:
mydbcount = Countdb.new(val1, val2, val3, val4, val5)



I'm sure I'm making a mess here... straighten me out guys..
-- 
Posted via http://www.ruby-forum.com/.