undefined method when returning an array in object.find(:all, :conditions)

Question

I'm using:

rails 2.3.9 ruby 1.9.3 windows 7 ultimate rubygems 1.8.24

This works:

@inventories = Inventory.find :first, :conditions => {:siteId => params[:siteId]}

This doesn't

@inventories = Inventory.find :all, :conditions => {:siteId => params[:siteId]}

Error message:

NoMethodError (undefined method `siteId' for #Array:0x49738f8)

score 1 · Accepted Answer · answered Sep 06 '12 at 07:53

1

For rails 2.x your syntax is slightly wrong If you want to find all records with certain conditions then try this example which uses multiple conditions

@inventories = Inventory.find(:all, :conditions => ["siteId=? and priority=?", params[:siteId], 3])

answered Sep 06 '12 at 07:53

jamesc

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i'd like the siteId to be the only condition. when i try: @inventories = Inventory.find(:all, :conditions => ["siteId=?", params[:siteId]]) the error persists. – Aldrin Dela Cruz Sep 06 '12 at 09:10
@AldrinDelaCruz I'm sure it did work. Perhaps the error is not on the find but on a line after the find. Post the full stack trace of your error from your development.log file – jamesc Sep 06 '12 at 14:57
yes james, i'm so sorry. it was in rendering the xml after executing this query. – Aldrin Dela Cruz Sep 07 '12 at 03:32

score 0 · Answer 2 · answered Sep 06 '12 at 08:17

when you write

@inventories = Inventory.find :first, :conditions => {:siteId => params[:siteId]}

Above line give you a single (first) object of the Inventory depending on the default order which matched the given condition so you can use @inventories.siteId. However when no row matches the given condition it will return nil and in such case if you try to use @inventories.siteId it will throws an error undefined methodsiteId' for nil`

But when you write

@inventories = Inventory.find :all, :conditions => {:siteId => params[:siteId]}

Above line gives you an array of the objects of Inventory no matters if your query returns the 1 or more than 1 objects i.e. row and blank array i.e [] if now rows satisfies the condition. So, when you try to use @inventories.siteId, you are actually applying siteId on Array and not on the object of Inventory and it will throws an error undefined methodsiteId' for #Array`. However following will work properly

@inventories.each{|p| puts "#{p.siteId}"}

this might be a noob question, but I'm trying to query all inventories with siteId = 17. — Aldrin Dela Cruz, Sep 06 '12 at 09:11

undefined method when returning an array in object.find(:all, :conditions)

2 Answers2