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I am certain this is very simple, but I'm a noob to Ruby and can't seem to find the answer to a very basic question.

I have a table with a list of words in PostgreSQL. I am getting a return value from a query to get a count of rows. When I try to assign this returned value to a variable "wordcount," I can't seem to get just the integer value. For example, if I try to use wordcount (as obtained below), Ruby throws an error "can't convert Array into Integer (TypeError)." In short, how do I convert the value obtained from the query to an integer? Thanks in advance.

q = 'SELECT COUNT(*) FROM words'
res  = conn.exec(q)
wordcount = res.values[0]
puts wordcount
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3 Answers 3

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Using PostgreSQL (and probably most other connectors), it would be:

wordcount = res[0]["count"]

are you sure you don't want to just do:

Word.count

though?

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Yep good spot - though I actually meant res[0]["count"]. And yep that's true, but thought it might be worth a mention given the OP's self-professed noobishness!
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The exec method returns a PGResult instance and PGResult#values:

Returns all tuples as an array of arrays.

So your res is an array of arrays: one entry for each row in the result set and each entry will itself be an array with one entry per column. They're strings as well, try this:

wordcount = res.getvalue(0, 0).to_i
puts wordcount
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The database library is giving you a return value that supports the return of multiple rows. You are probably getting an array with a single row that contains an array with a single column that takes your value.

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