RubyOnRails
15 八月 2010 | View Comments
In this commit we found we big improvement.
They add :inverse_of for active_record association
What is that used for?
Here is the example from commit message
class Man < ActiveRecord::Base
has_one :face, :inverse_of => :man
end
class Face < ActiveRecord::Base
belongs_to :man, :inverse_of => :face
end
m = Man.first
f = m.face
If we don’t have :inverse_of, f.man will be different object, not m@ object and what's more active_record will fire another sql query if you can @f.man.
After we add :inverse_of option, @ m == f.man , and @f.man will not fire a sql query.
But now :inverse_of only works for has_one, has_many. It also supplies inverse support for belongs_to
associations where the inverse is a has_one and it’s not a polymorphic.
I think DataMapper need change their website why DataMapper. Active Record has Identity Map now
Thanks
h-lame for giving us this very useful feature which also have sufficient test.
Tagged in 2.3.6, active_record, inverse_of, RubyOnRails
RubyOnRails
15 八月 2010 | View Comments
In this commit rails team improved redirect_to method, we can passing flash option directly.
# ... in an action
#old style
flash[:notice] = "Pay attention to the road"
redirect_to post_url(@post)
#new way
redirect_to post_url(@post), :notice => "Pay attention to the road"
They also add some convenient methods for flash object. Now you can get/set flash object in view by
alert,alert=(message),notice,notice=(message)
Tagged in 2.3.6, active_controller, flash, RubyOnRails
RubyOnRails
31 七月 2010 | View Comments
In this commit Rails add a new feature that we can specify what’s the postillion to add a column.
# In migration
# add column to in first position
add_column :testings, :new_col, :integer, :first => true
# add column after another column
add_column :testings, :new_col, :integer, :after => "column_a"
# change a column with position
change_column :testings, :second, :integer, :first => true
change_column :testings, :second, :integer, :after => "column_c"
About how column position affect performance, you can see this blog post
Thanks bmarini commit this feature, also thanks jeremy reviewed this commit.
Tagged in 2.3.6, RubyOnRails
