How to select where ID in Array Rails ActiveRecord without exception

Question

When I have array of ids  like  ids    2 3 5    and I perform  Comment find ids    everything works fine  But when there is id that doesn t exist  I get an exception  This occurs generaly when I get list of IDs that match some filter and than I do something like  current user comments find ids    This time I may have a valid comment ID  which however does not belong to given User  so it is not found and I get an exception   I ve tried find  all  ids   but it returns all of the records   The only way I can do it now is  current user comments select    c  ids include  c id      But that seems to me like super inefficient solution   Is there better way to select ID in Array without getting exception on non-existing record

User · Answer

To avoid exceptions killing your app you should catch those exceptions and treat them the way you wish, defining the behavior for you app on those situations where the id is not found.

begin
  current_user.comments.find(ids)
rescue
  #do something in case of exception found
end

Here's more info on exceptions in ruby.

User · Answer

Update  This answer is more relevant for Rails 4 x  Do this   current user comments where  id  gt  123  456   Michael Jackson      The stronger side of this approach is that it returns a Relation object  to which you can join more  where clauses   limit clauses  etc   which is very helpful  It also allows non-existent IDs without throwing exceptions   The newer Ruby syntax would be   current user comments where id   123   456    Michael Jackson

User · Answer

If you need more control  perhaps you need to state the table name  you can also do the following    Model joins  another model table name     where  another model table name id IN       your id array

User · Answer

If it is just avoiding the exception you are worried about  the  find all by    family of functions works without throwing exceptions   Comment find all by id  2  3  5     will work even if some of the ids don t exist   This works in the   user comments find all by id potentially nonexistent ids    case as well   Update  Rails 4  Comment where id   2  3  5

User · Answer

Now  find and  find by id methods are deprecated in rails 4  So instead we can use below   Comment where id   2  3  5     It will work even if some of the ids don t exist  This works in the  user comments where id  avoided ids array    Also for excluding ID s  Comment where not id   2  3  5

User · Answer

You can also use it in named scope if You want to put there others conditions  for example include some other model      named scope  get by ids    lambda    ids     include      comments    conditions      comments id IN       ids

[ruby-on-rails] How to select where ID in Array Rails ActiveRecord without exception

Examples related to ruby-on-rails

Examples related to activerecord

Examples related to find