# Complex Finds -- find\_by\_sql?

**URL:** <https://www.ruby-forum.com/t/complex-finds-find-by-sql/172916>\
**Category:** Rails\
**Created:** [July 29, 2009, 11:30pm UTC](https://www.ruby-forum.com/t/complex-finds-find-by-sql/172916 "2009-07-29T23:30:55Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![josh](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/45deac/32.png) [@josh](https://www.ruby-forum.com/u/josh)\
**Post date:** [July 29, 2009, 11:30pm UTC](https://www.ruby-forum.com/t/complex-finds-find-by-sql/172916/1 "2009-07-29T23:30:55Z")

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I have been working with an ever scope creeping application which  
requires very deeply nested database relations find/select statements.  
I’ve taken in more than a few cases (where optimization is needed) to  
using find\_by\_sql(“select \* … join, count, where , etc”) when  
sticking to builtin rails finder options become inefficient or unable  
to process the queries. I am aware that sometimes I use find\_by\_sql  
just because I don’t have the time to try to figure out the rails way  
and writing queries is just simpler and quicker. Every time I do I am  
am impressed at the query optimization, but I always have a feeling of  
guilt over it that I just can’t shake!

Ideally I would like to know if these sql queries are going to scale  
to other dbs query languages. Do other people find themselves doing  
the same thing? I think it would be great if there were a sql tester  
that would tell you that syntax or operational order could be  
ambiguous depending on what db software is being implemented. Anyone  
know of such a thing, or perhaps have a good set of guidelines that  
keeps queries compatible?

-Josh

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<div class="post-metadata">

**Author:** ![josh](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/45deac/32.png) [@josh](https://www.ruby-forum.com/u/josh)\
**Post date:** [July 29, 2009, 11:41pm UTC](https://www.ruby-forum.com/t/complex-finds-find-by-sql/172916/2 "2009-07-29T23:41:28Z")

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On Wed, Jul 29, 2009 at 4:29 PM, Josh[removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote:

> guilt over it that I just can’t shake!
> 
> Ideally I would like to know if these sql queries are going to scale  
> to other dbs query languages. Do other people find themselves doing  
> the same thing? I think it would be great if there were a sql tester  
> that would tell you that syntax or operational order could be  
> ambiguous depending on what db software is being implemented. Anyone  
> know of such a thing, or perhaps have a good set of guidelines that  
> keeps queries compatible?

If you’re having to write SQL your models are likely not associated  
correctly.

Make sure to use the :select option in your find calls, otherwise you  
get the default SELECT \*.

Your raw SQL may work on another db if it’s simple, but not having any  
SQL will of course be the completely portable option.

–  
Greg D.  
[http://destiney.com/](http://destiney.com/)