# Creating queries

**URL:** <https://www.ruby-forum.com/t/creating-queries/65403>\
**Category:** Rails\
**Created:** [August 17, 2006, 11:21pm UTC](https://www.ruby-forum.com/t/creating-queries/65403 "2006-08-17T23:21:27Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![mohits](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/bbe5ce/32.png) [@mohits](https://www.ruby-forum.com/u/mohits)\
**Post date:** [August 17, 2006, 11:21pm UTC](https://www.ruby-forum.com/t/creating-queries/65403/1 "2006-08-17T23:21:27Z")

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Hi, I am trying to implement a few queries now. What are good ways to do  
this?

Right now, I have a list page that does sorting and can carry out a  
generic pagination request.  
@user\_result\_pages, @user\_results = paginate(:user\_results,  
:per\_page =\> 20,  
:conditions =\> @condition,  
:order\_by =\> @sort\_order)

I create @sort\_order earlier in the list function. The problem I am  
having is with ‘@condition’ I’m not sure what’s the best way to create  
this. There are a number of options that my user may select:

1. date \> …
2. range of dates
3. specific dates
4. name is LIKE …  
and so on…

I’m therefore having trouble conceptualizing how to create this  
condition string. All the examples I have seen so far talk about it as  
:conditions =\> [?created\_on \> ??, time] and so on. I can’t find an  
example that helps me formulate this string earlier.

Another example I saw uses ‘sanitize’ which seems to be available in the  
model but not the controller, so I can’t seem to use that either.

Help would be greatly appreciated 😃  
Thanks  
Mohit.

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<div class="post-metadata">

**Author:** ![mohits](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/bbe5ce/32.png) [@mohits](https://www.ruby-forum.com/u/mohits)\
**Post date:** [August 18, 2006, 12:15am UTC](https://www.ruby-forum.com/t/creating-queries/65403/2 "2006-08-18T00:15:33Z")

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A good way to start is to remember that :conditions is not a String but  
an Array.  
The first index of the :conditions is the sqlish query which can be  
built anyway you  
see fit and the arguments can then be added (+) to it to create the  
final :conditions  
Array. :conditions =\> [query string with ?] + [arugment1]

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<div class="post-metadata">

**Author:** ![mohits](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/bbe5ce/32.png) [@mohits](https://www.ruby-forum.com/u/mohits)\
**Post date:** [August 18, 2006, 6:28am UTC](https://www.ruby-forum.com/t/creating-queries/65403/3 "2006-08-18T06:28:35Z")

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Thanks, Todd! That helped me to get started 🙂  
Cheers  
Mohit.

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<div class="post-metadata">

**Author:** ![mohits](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/bbe5ce/32.png) [@mohits](https://www.ruby-forum.com/u/mohits)\
**Post date:** [August 18, 2006, 6:52am UTC](https://www.ruby-forum.com/t/creating-queries/65403/4 "2006-08-18T06:52:40Z")

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Hi again! I am able to create the query string correctly now for the  
conditions. I’d like to use my common list function to show the  
records. So, what I’d like to do is call a set of different functions  
that create the correct search conditions based on what is entered in  
the forms.

But, although I’m able to construct the query in a controller function  
called ‘query1’ - unfortunately this does not work:

def q2  
id = params[:id]

```
  qa = ['name like ?']
  sid = '%' + params[:name] + '%'
  @qp = [sid]
  qa << 'test_date >= ?'
  @qp << params[:start]
  @condition = [qa.join(' and ')] + @qp

  params[:condition] = @condition
  redirect_to :action => 'list2'

```

end

I’m confused whether I should use:  
redirect\_to :action =\> ‘list2’  
or  
render :action =\> ‘list2’

On the other side, list2 picks it up and uses it for the pagination (if  
I put the above code into list2 it works fine)  
@condition = params[:condition]  
@kx21\_result\_pages, @kx21\_results = paginate(:kx21\_results,  
:per\_page =\> 20,  
:conditions =\>  
@condition,  
:order\_by =\>  
@sort\_order)

How do I pass the conditions array as a parameter to the redirect?

It does work if I ‘render :action =\> list2’ into the function that  
creates the query (q2 above) - but, then I must duplicate the code that  
checks and creates the strings for the sort order, etc… I guess I  
could DRY it up?

Is it a good idea to break up my queries in such a manner?  
Thanks  
Mohit.