# Query the :limit =\> value back out of the schema

**URL:** <https://www.ruby-forum.com/t/query-the-limit-value-back-out-of-the-schema/170215>\
**Category:** Rails\
**Created:** [June 14, 2009, 6:02am UTC](https://www.ruby-forum.com/t/query-the-limit-value-back-out-of-the-schema/170215 "2009-06-14T06:02:58Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![Phlip](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/ed8c4c/32.png) [@Phlip](https://www.ruby-forum.com/u/Phlip)\
**Post date:** [June 14, 2009, 6:02am UTC](https://www.ruby-forum.com/t/query-the-limit-value-back-out-of-the-schema/170215/1 "2009-06-14T06:02:58Z")

</div>

Railsters:

My evil colleagues could migrate the :limit=\> on an important string at  
any  
time. (Think Twitter’s infamous string :limit =\> 140.)

I don’t want to guess that limit and hard-code it into the program; I  
want to  
read it back out of the ActiveRecord field properties. How to navigate  
to them?

–  
Phlip

---

<div class="post-metadata">

**Author:** ![Phlip](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/ed8c4c/32.png) [@Phlip](https://www.ruby-forum.com/u/Phlip)\
**Post date:** [June 14, 2009, 11:32am UTC](https://www.ruby-forum.com/t/query-the-limit-value-back-out-of-the-schema/170215/2 "2009-06-14T11:32:08Z")

</div>

Let’s say you have a model Foo, and you want the length of a column  
“bar” - then this will do what you want:

Foo.columns.find { |c| c.name == ‘bar’ }.limit

–Matt J.

---

<div class="post-metadata">

**Author:** ![Phlip](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/ed8c4c/32.png) [@Phlip](https://www.ruby-forum.com/u/Phlip)\
**Post date:** [June 16, 2009, 1:09am UTC](https://www.ruby-forum.com/t/query-the-limit-value-back-out-of-the-schema/170215/3 "2009-06-16T01:09:44Z")

</div>

Matt J. wrote:

> Foo.columns.find { |c| c.name == ‘bar’ }.limit

Tx it worked! And you can even set a “constant” on it…

–  
Phlip