# Set a default value to a "text/blob" field at creation? **URL:** \ **Category:** Rails\ **Created:** [April 3, 2008, 11:15am UTC](https://www.ruby-forum.com/t/set-a-default-value-to-a-text-blob-field-at-creation/133763 "2008-04-03T11:15:59Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![kaizerkaizer](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/k/45deac/32.png) [@kaizerkaizer](https://www.ruby-forum.com/u/kaizerkaizer)\ **Post date:** [April 3, 2008, 11:15am UTC](https://www.ruby-forum.com/t/set-a-default-value-to-a-text-blob-field-at-creation/133763/1 "2008-04-03T11:15:59Z")
Is it possible somehow to incorporate “this is a text” into a “blob/text”-value in the database when the row is created? It’s not possible to do with a default value hence it’s a “blob/text”-value. At the moment I create the row for a user with: @presentation = current\_user.presentation @presentation = current\_user.create\_presentation unless @presentation ---
**Author:** ![kaizerkaizer](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/k/45deac/32.png) [@kaizerkaizer](https://www.ruby-forum.com/u/kaizerkaizer)\ **Post date:** [April 3, 2008, 2:40pm UTC](https://www.ruby-forum.com/t/set-a-default-value-to-a-text-blob-field-at-creation/133763/2 "2008-04-03T14:40:40Z")
I tried to create this in my lib file string.rb to show something else if the value was nil…(and required the ‘string.rb’ in my application helper) def or\_empty(alternate) (self.nil? or self == “”) ? alternate : self end but that didn’t work either. ---
**Author:** ![kaizerkaizer](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/k/45deac/32.png) [@kaizerkaizer](https://www.ruby-forum.com/u/kaizerkaizer)\ **Post date:** [April 4, 2008, 11:08am UTC](https://www.ruby-forum.com/t/set-a-default-value-to-a-text-blob-field-at-creation/133763/3 "2008-04-04T11:08:32Z")
Julian L. wrote: > You’d need to open the class up to do this. > > class String > def or\_empty(alternate = ‘default’) > self.blank? ? alternate : self > end > > That would work. > > Julian. > > Learn Ruby on Rails! CHECK OUT THE FREE VIDS (LIMITED TIME) VIDEO #3 > OUT APRIL 6 > [http://sensei.zenunit.com/](http://sensei.zenunit.com/) Nope, that doesn’t do it, I still get an error “The error occurred while evaluating nil.or\_empty” in this line of my show-view: \<%= h @presentation.pres.or\_empty(“No presentation has been entered”)%\> because the there exists nothing in the pres-field. This is what I’m trying to fix. what do you mean with: > You’d need to open the class up to do this. ---
**Author:** ![kaizerkaizer](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/k/45deac/32.png) [@kaizerkaizer](https://www.ruby-forum.com/u/kaizerkaizer)\ **Post date:** [April 4, 2008, 2:13am UTC](https://www.ruby-forum.com/t/set-a-default-value-to-a-text-blob-field-at-creation/133763/4 "2008-04-04T02:13:51Z")
You’d need to open the class up to do this. class String def or\_empty(alternate = ‘default’) self.blank? ? alternate : self end That would work. Julian. Learn Ruby on Rails! CHECK OUT THE FREE VIDS (LIMITED TIME) VIDEO #3 OUT APRIL 6 [http://sensei.zenunit.com/](http://sensei.zenunit.com/) ---
**Author:** ![kaizerkaizer](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/k/45deac/32.png) [@kaizerkaizer](https://www.ruby-forum.com/u/kaizerkaizer)\ **Post date:** [April 4, 2008, 11:47am UTC](https://www.ruby-forum.com/t/set-a-default-value-to-a-text-blob-field-at-creation/133763/5 "2008-04-04T11:47:08Z")
Frederick C. wrote: > On 4 Apr 2008, at 10:08, Dag S. wrote: > > > because the there exists nothing in the pres-field. This is what I’m > > trying to fix. > > How about you do this in your model > > def pres > value\_in\_database = self[:pres] > #do something with value\_in\_database > end > > Fred I’m not quite sure I completely understand… =/ ---
**Author:** ![kaizerkaizer](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/k/45deac/32.png) [@kaizerkaizer](https://www.ruby-forum.com/u/kaizerkaizer)\ **Post date:** [April 4, 2008, 11:59am UTC](https://www.ruby-forum.com/t/set-a-default-value-to-a-text-blob-field-at-creation/133763/6 "2008-04-04T11:59:16Z")
On 4 Apr 2008, at 10:47, Dag S. wrote: > > #do something with value\_in\_database > > end > > > > Fred > > I’m not quite sure I completely understand… =/ Overwrite the accessor that rails provides, using self[:pres] to get at the original value. Fred ---
**Author:** ![kaizerkaizer](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/k/45deac/32.png) [@kaizerkaizer](https://www.ruby-forum.com/u/kaizerkaizer)\ **Post date:** [April 4, 2008, 11:21am UTC](https://www.ruby-forum.com/t/set-a-default-value-to-a-text-blob-field-at-creation/133763/7 "2008-04-04T11:21:52Z")
On 4 Apr 2008, at 10:08, Dag S. wrote: > because the there exists nothing in the pres-field. This is what I’m > trying to fix. How about you do this in your model def pres value\_in\_database = self[:pres] #do something with value\_in\_database end Fred ---
**Author:** ![kaizerkaizer](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/k/45deac/32.png) [@kaizerkaizer](https://www.ruby-forum.com/u/kaizerkaizer)\ **Post date:** [April 4, 2008, 1:19pm UTC](https://www.ruby-forum.com/t/set-a-default-value-to-a-text-blob-field-at-creation/133763/8 "2008-04-04T13:19:28Z")
Frederick C. wrote: > On 4 Apr 2008, at 10:47, Dag S. wrote: > > > > #do something with value\_in\_database > > > end > > > > > > Fred > > > > I’m not quite sure I completely understand… =/ > > Overwrite the accessor that rails provides, using self[:pres] to get > at the original value. > > Fred Alright, thanx a lot, solved the problem!