Activerecord memo (3)

ActiveRecord::Base
save, save!, create, create!, update_attribute, update_attributes, update, update_all, delete, delete_all, destroy, destroy_all

1. save vs save!
save 成功 => true
save 失敗 => fasle

另外 save(perform_validation = true), save 還可以丟個參數進去, save(false) 的話, 一堆validate 都不跑, 可是會跑before_*, 失敗一樣是return false

save! 成功 => true
save! 失敗 => validate 失敗：RecordInvalid execption,
before_* 失敗 : RecordNotSaved

---

2. create vs create!
create 成功 => ActiveRecord object
<br />>> f = Forum.create(:subject => 'jaifjai', :content => 'fhauehf', :user_id => 3)<br />=> #<Forum id: 29, subject: "jaifjai", content: "fhauehf", created_at: "2009-02-05 10:22:55", user_id: 3, comments_count: 0, group_id: nil, last_comment_time: "2009-02-05 10:22:55", public: nil><br />

create 失敗 => ActiveRecord object, 所以要確認成功失敗可以用 errors.empty? 檢查
<br />=> #<Forum id: nil, subject: "jaifjai", content: nil, created_at: nil, user_id: nil, comments_count: 0, group_id: nil, last_comment_time: nil, public: nil><br /><br />>> f.errors<br />=> #<ActiveRecord::Errors:0xb70289f8 @errors={"content"=>["can't be blank"]}, @base=#<Forum id: nil, subject: "jaifjai", content: nil, created_at: nil, user_id: nil, comments_count: 0, group_id: nil, last_comment_time: nil, public: nil>><br /><br />>> f.errors.empty?<br />=> false<br />

create! 成功 => ActiveRecord object
create! 失敗 => RecordInvalid

---

3. 如果是資料庫的validate 就會爆 StatementInvalid
例如有這樣的設定 t.column :user_id, :integer, :null => false
沒填user_id 就會爆StatementInvalid

---

4. update_attribute vs update_attributes
除了可以更新update的多寡之外,
還有 update_attribute 是 save(false), 它不跑 validate

同樣成功true, 失敗false

---

5 update, update_all
丟的參數差很多
update(id, attributes)
update_all(updates, conditions = nil, options = {})
<br /> Forum.update([6,7], [{:user_id => 2}, {:user_id => 3}])<br /><br /> # Updating multiple records:<br /> people = { 1 => { "first_name" => "David" }, 2 => { "first_name" => "Jeremy" } }<br /> Person.update(people.keys, people.values)<br /><br /> # Update all billing objects with the 3 different attributes given<br /> Billing.update_all( "category = 'authorized', approved = 1, author = 'David'" )<br /><br /> # Update records that match our conditions<br /> Billing.update_all( "author = 'David'", "title LIKE '%Rails%'" )<br /><br /> # Update records that match our conditions but limit it to 5 ordered by date<br /> Billing.update_all( "author = 'David'", "title LIKE '%Rails%'",<br /> :order => 'created_at', :limit => 5 )<br />

---

6.delete_all, delete, destroy, destroy_all
delete 是不會跑before_, after_ destroy 還有 dependent 也是不跑的

destroy_all(conditions = nil)
delete_all(conditions = nil)
<br /> #delete, destroy 也可以這樣用<br /> # Delete a single row<br /> Todo.delete(1)<br /><br /> # Delete multiple rows<br /> Todo.delete([2,3,4])<br /><br /> # Destroy a single object<br /> Todo.destroy(1)<br /><br /> # Destroy multiple objects<br /> todos = [1,2,3]<br /> Todo.destroy(todos)<br />

---

7. ConnectionAdapters::DatabaseStatements

connection.select_all

---

8. ActiveRecord::ConnectionAdapters::AbstractAdapter

ActiveRecord::Base.connection returns an AbstractAdapter object,

svn, update

http://svnbook.red-bean.com/en/1.0/re28.html
You can also update your working copy to an older revision

svn update -r30

---

svn diff -rPREV
svn diff file_name -rPREV
svn log --limit
svn log --limit 2 main.css
svn cat -r5323 show.rhtml

svn merge -r7311:7389 svn://svn.icetech.com.tw/serac/youholder/branches/haruko
svn import earlybirds/ svn://bigcat.dlinkddns.com/eb/trunk

rjs update layout

http://www.codefluency.com/articles/2006/05/27/rails-views-render-update-not-rjs/
http://www.scribd.com/doc/220397/RJShow-it-works
http://api.rubyonrails.org/classes/ActionView/Helpers/PrototypeHelper/JavaScriptGenerator/GeneratorMethods.html
http://api.rubyonrails.org/classes/ActionView/Helpers/PrototypeHelper.html

[test rjs]
page.you_holder.cde

[application.js]
YouHolder.cde = function(){
(function($){
 alert('lalala');
 })(jQuery);
}



layout proc{ |c| c.request.xhr? ? false : "application" } 

render page update

[view]
   function ajax_create(act, pos, goals) {
     $.ajax({
        url:  '/goals/'+act,
        type: 'POST',
        data: goals,
        dataType:  'html',
        success:function(html){
          $(pos).after(html);
          $('td.goal_del').unbind('click', goal_del).bind('click', goal_del);
          $('td.goal_up_tmp').unbind('click', goal_up ).bind('click', goal_up);
          $('td.goal_down_tmp').unbind('click', goal_down).bind('click', goal_down);
        }
      });
   }

[controller]
render :partial => 'member/temp_goal', :locals => {:g => new_goal}


[view]
<%= observe_field :target_type_target_type_id,     :on => "change",
  :url => {:action => :update_target_list},
  :with => "{target_type_id: value, target_cat_id: $('target_type_target_cat_id').value}"%>

(用page 寫 js)
[controller]
  render :update do |page|
    page.replace_html 'target_type_target_id', :partial => 'target_type_select', :locals => {:types => target_list}
  end


[view]
   function test() {
     $.ajax({
        url:  '/alert/test',
        type: 'GET',
        success : function(html){
          alert(html);
        }
      });
   }

[controller]
    render :action => 'test', :layout => false

[test view]
<% response.headers['Content-Type'] = "text/javascript" %>
alert(<%=1+1 %>);



[view]
   function test() {
     $.ajax({
        url:  '/alert/test',
        type: 'GET',
        dataType:  'script'
      });
   }

[controller]
render :action => 'test', :layout => false

[test view]
<% response.headers['Content-Type'] = "text/javascript" %>
alert(<%=1+1 %>);



[view]
   function test() {
     $.ajax({
        url:  '/alert/test',
        type: 'GET',
        dataType:  'script'
      });
   }

[controller]
  render :update do |page|
    page.alert('cccccc')  #page << "alert('cccc');"   the same     end 



[view]
   function test() {
     $.ajax({
        url:  '/alert/test',
        type: 'GET',
        dataType:  'script'
      });
   }

[controller]
  def test
     #nothing
  end
[test view]  test.rjs
  page << "alert('cccccc');"

update, replace_html

http://api.rubyonrails.org/classes/ActionView/Helpers/PrototypeHelper/JavaScriptGenerator/GeneratorMethods.html#M001645
replace_html可以用partial 去取代

   render :update do |page|
     page.replace_html 'target_type_target_type_id',
                       :partial => 'target_type_select', :locals => {:types => target_type_content}
   end