[cfgeeks] OK calling in the cavalry

[Gilbert Young]

On Jan 1, 2007, at 10:24 AM, Steve Litt wrote:

> On Monday 01 January 2007 02:30, Gilbert Young wrote:
>> Ruby Q.  I am trying to compare two variables that are strings, one
>> taken from a SQL command, one taken from user input earlier (ticker):
>
> Hi Gil,
>
> IIRC in Ruby == on two strings measures whether they reference the  
> same
> variable, not whether their value is the same. There's some  
> string.equal() or
> something like that, that does what you want. I'd look it up but  
> I'm about to
> begin a 1200 mile car trip with my family of 5 from Chicago to  
> Orlando.
>
> SteveT


Thanks Steve,

That was partially it, I found the way to compare string to string,  
variable.equ?(variable2) returns either true or false.   But then, I  
started getting this error:

testthedb.rb:24:in `+': can't convert DBI::Row into String (TypeError)

It appears the silent issue I was having was that I was trying to  
compare a string to a DBI::Row, and they would never match.

Solution was to convert the variable that was a DBI::Row to a string  
using variable.to_s (variable.to_str did not work), and then compare:

sth = dbh.execute("SHOW TABLES LIKE '#{ticker}'")
tr = sth.fetch
aaa = tr.to_s
result = ticker.eql?(aaa)
puts result
if result
puts "table #{ticker} exists"
else
puts "table #{ticker} does not exist"
end
sth.finish


The latest run resulted in this:

gilbert-youngs-powerbook-g4-12:~/projects/stock gjy$ ruby testthedb.rb
Enter ticker symbol: lksdf

false
table lksdf does not exist
gilbert-youngs-powerbook-g4-12:~/projects/stock gjy$ ruby testthedb.rb
Enter ticker symbol: testtable

true
table testtable exists
gilbert-youngs-powerbook-g4-12:~/projects/stock gjy$

Now i'm going to try and pretty it up and comment the code so I don't  
forget what I had to do to get it to work :).