# ODBC and Ruby

**URL:** <https://www.ruby-forum.com/t/odbc-and-ruby/121081>\
**Category:** Ruby\
**Created:** [November 23, 2007, 2:55pm UTC](https://www.ruby-forum.com/t/odbc-and-ruby/121081 "2007-11-23T14:55:48Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![lorenzo](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/l/4da419/32.png) [@lorenzo](https://www.ruby-forum.com/u/lorenzo)\
**Post date:** [November 23, 2007, 2:55pm UTC](https://www.ruby-forum.com/t/odbc-and-ruby/121081/1 "2007-11-23T14:55:48Z")

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hello, I’m new in ruby, I’ve problems conneting ruby odbc with informix  
db, in tbles with thousand records my program always retruns no rows,

this is the test program:

sth=c.prepare(“select \* from anopta”)

sth.execute  
if sth.ncols == 0 then  
puts “Statement has no result set”  
printf “Number of rows affected: %d\n”, sth.nrows  
else  
puts “Statement has a result set”  
sth.fetch\_all  
printf “Number of rows: %d\n”, sth.nrows  
printf “Number of columns: %d\n”, sth.ncols  
end

this is the output

Statement has a result set  
Number of rows: -1  
Number of columns: 5

The table has 5 colums and 300 rows

I don’t know if this problem is specific for informix databases

thank u very much

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<div class="post-metadata">

**Author:** ![lorenzo](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/l/4da419/32.png) [@lorenzo](https://www.ruby-forum.com/u/lorenzo)\
**Post date:** [November 23, 2007, 5:32pm UTC](https://www.ruby-forum.com/t/odbc-and-ruby/121081/2 "2007-11-23T17:32:55Z")

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Hello Lorenzo,

On Nov 23, 2007 7:55 AM, lorenzo [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote:

> ```
> printf "Number of rows affected: %d\n", sth.nrows
> 
> ```
> 
> Statement has a result set  
> Number of rows: -1  
> Number of columns: 5
> 
> The table has 5 colums and 300 rows
> 
> I don’t know if this problem is specific for informix databases
> 
> thank u very much

May I suggest you to try the Informix extension instead?

[http://ruby-informix.rubyforge.org](http://ruby-informix.rubyforge.org)

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<div class="post-metadata">

**Author:** ![lorenzo](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/l/4da419/32.png) [@lorenzo](https://www.ruby-forum.com/u/lorenzo)\
**Post date:** [November 23, 2007, 6:23pm UTC](https://www.ruby-forum.com/t/odbc-and-ruby/121081/3 "2007-11-23T18:23:23Z")

</div>

On 2007-11-23 17:32:25 +0100, Gerardo S. Gómez Garrido  
[removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) said:  
Hello,  
Is not so easy, I’m using Macosx and I don’ have informix sdk for it  
Have you any ideas?  
Thank you 🙂

---

<div class="post-metadata">

**Author:** ![lorenzo](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/l/4da419/32.png) [@lorenzo](https://www.ruby-forum.com/u/lorenzo)\
**Post date:** [November 23, 2007, 6:51pm UTC](https://www.ruby-forum.com/t/odbc-and-ruby/121081/4 "2007-11-23T18:51:01Z")

</div>

On Nov 23, 2007 11:20 AM, lorenzo [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote:

> On 2007-11-23 17:32:25 +0100, Gerardo S. Gómez Garrido  
> [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) said:  
> Hello,  
> Is not so easy, I’m using Macosx and I don’ have informix sdk for it

I see.

> Have you any ideas?  
> Thank you 🙂

Yes. I have just remembered (I used to use ruby-odbc with Informix two  
years ago) that nrows didn’t return any useful value to me for  
Informix. Ignore it. You can’t know how many records a SELECT returns  
in Informix before fetching them.

---

<div class="post-metadata">

**Author:** ![lorenzo](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/l/4da419/32.png) [@lorenzo](https://www.ruby-forum.com/u/lorenzo)\
**Post date:** [November 23, 2007, 8:21pm UTC](https://www.ruby-forum.com/t/odbc-and-ruby/121081/5 "2007-11-23T20:21:18Z")

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On 2007-11-23 18:50:22 +0100, Gerardo S. Gómez Garrido  
[removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) said:

> Yes. I have just remembered (I used to use ruby-odbc with Informix two  
> years ago) that nrows didn’t return any useful value to me for  
> Informix. Ignore it. You can’t know how many records a SELECT returns  
> in Informix before fetching them.

Yes, but querying the table, the rs seems to be empty, ruby give me  
warning message for no methods for NilClass in each. So I supose the rs  
is empty, anywhere nrows doesn’t work you are right.