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Diffstat (limited to 'activerecord/lib/active_record/base.rb')
| -rwxr-xr-x | activerecord/lib/active_record/base.rb | 116 |
1 files changed, 1 insertions, 115 deletions
diff --git a/activerecord/lib/active_record/base.rb b/activerecord/lib/active_record/base.rb index c20a14551e..6063c9789f 100755 --- a/activerecord/lib/active_record/base.rb +++ b/activerecord/lib/active_record/base.rb @@ -556,124 +556,10 @@ module ActiveRecord #:nodoc: end alias :colorize_logging= :colorize_logging - # Find operates with four different retrieval approaches: - # - # * Find by id - This can either be a specific id (1), a list of ids (1, 5, 6), or an array of ids ([5, 6, 10]). - # If no record can be found for all of the listed ids, then RecordNotFound will be raised. - # * Find first - This will return the first record matched by the options used. These options can either be specific - # conditions or merely an order. If no record can be matched, +nil+ is returned. Use - # <tt>Model.find(:first, *args)</tt> or its shortcut <tt>Model.first(*args)</tt>. - # * Find last - This will return the last record matched by the options used. These options can either be specific - # conditions or merely an order. If no record can be matched, +nil+ is returned. Use - # <tt>Model.find(:last, *args)</tt> or its shortcut <tt>Model.last(*args)</tt>. - # * Find all - This will return all the records matched by the options used. - # If no records are found, an empty array is returned. Use - # <tt>Model.find(:all, *args)</tt> or its shortcut <tt>Model.all(*args)</tt>. - # - # All approaches accept an options hash as their last parameter. - # - # ==== Parameters - # - # * <tt>:conditions</tt> - An SQL fragment like "administrator = 1", <tt>[ "user_name = ?", username ]</tt>, or <tt>["user_name = :user_name", { :user_name => user_name }]</tt>. See conditions in the intro. - # * <tt>:order</tt> - An SQL fragment like "created_at DESC, name". - # * <tt>:group</tt> - An attribute name by which the result should be grouped. Uses the <tt>GROUP BY</tt> SQL-clause. - # * <tt>:having</tt> - Combined with +:group+ this can be used to filter the records that a <tt>GROUP BY</tt> returns. Uses the <tt>HAVING</tt> SQL-clause. - # * <tt>:limit</tt> - An integer determining the limit on the number of rows that should be returned. - # * <tt>:offset</tt> - An integer determining the offset from where the rows should be fetched. So at 5, it would skip rows 0 through 4. - # * <tt>:joins</tt> - Either an SQL fragment for additional joins like "LEFT JOIN comments ON comments.post_id = id" (rarely needed), - # named associations in the same form used for the <tt>:include</tt> option, which will perform an <tt>INNER JOIN</tt> on the associated table(s), - # or an array containing a mixture of both strings and named associations. - # If the value is a string, then the records will be returned read-only since they will have attributes that do not correspond to the table's columns. - # Pass <tt>:readonly => false</tt> to override. - # * <tt>:include</tt> - Names associations that should be loaded alongside. The symbols named refer - # to already defined associations. See eager loading under Associations. - # * <tt>:select</tt> - By default, this is "*" as in "SELECT * FROM", but can be changed if you, for example, want to do a join but not - # include the joined columns. Takes a string with the SELECT SQL fragment (e.g. "id, name"). - # * <tt>:from</tt> - By default, this is the table name of the class, but can be changed to an alternate table name (or even the name - # of a database view). - # * <tt>:readonly</tt> - Mark the returned records read-only so they cannot be saved or updated. - # * <tt>:lock</tt> - An SQL fragment like "FOR UPDATE" or "LOCK IN SHARE MODE". - # <tt>:lock => true</tt> gives connection's default exclusive lock, usually "FOR UPDATE". - # - # ==== Examples - # - # # find by id - # Person.find(1) # returns the object for ID = 1 - # Person.find(1, 2, 6) # returns an array for objects with IDs in (1, 2, 6) - # Person.find([7, 17]) # returns an array for objects with IDs in (7, 17) - # Person.find([1]) # returns an array for the object with ID = 1 - # Person.find(1, :conditions => "administrator = 1", :order => "created_on DESC") - # - # Note that returned records may not be in the same order as the ids you - # provide since database rows are unordered. Give an explicit <tt>:order</tt> - # to ensure the results are sorted. - # - # ==== Examples - # - # # find first - # Person.find(:first) # returns the first object fetched by SELECT * FROM people - # Person.find(:first, :conditions => [ "user_name = ?", user_name]) - # Person.find(:first, :conditions => [ "user_name = :u", { :u => user_name }]) - # Person.find(:first, :order => "created_on DESC", :offset => 5) - # - # # find last - # Person.find(:last) # returns the last object fetched by SELECT * FROM people - # Person.find(:last, :conditions => [ "user_name = ?", user_name]) - # Person.find(:last, :order => "created_on DESC", :offset => 5) - # - # # find all - # Person.find(:all) # returns an array of objects for all the rows fetched by SELECT * FROM people - # Person.find(:all, :conditions => [ "category IN (?)", categories], :limit => 50) - # Person.find(:all, :conditions => { :friends => ["Bob", "Steve", "Fred"] } - # Person.find(:all, :offset => 10, :limit => 10) - # Person.find(:all, :include => [ :account, :friends ]) - # Person.find(:all, :group => "category") - # - # Example for find with a lock: Imagine two concurrent transactions: - # each will read <tt>person.visits == 2</tt>, add 1 to it, and save, resulting - # in two saves of <tt>person.visits = 3</tt>. By locking the row, the second - # transaction has to wait until the first is finished; we get the - # expected <tt>person.visits == 4</tt>. - # - # Person.transaction do - # person = Person.find(1, :lock => true) - # person.visits += 1 - # person.save! - # end - def find(*args) - options = args.extract_options! - - relation = construct_finder_arel(options, current_scoped_methods) - - case args.first - when :first, :last, :all - relation.send(args.first) - else - relation.find(*args) - end - end - + delegate :find, :first, :last, :all, :to => :scoped delegate :select, :group, :order, :limit, :joins, :where, :preload, :eager_load, :includes, :from, :lock, :readonly, :having, :to => :scoped delegate :count, :average, :minimum, :maximum, :sum, :calculate, :to => :scoped - # A convenience wrapper for <tt>find(:first, *args)</tt>. You can pass in all the - # same arguments to this method as you can to <tt>find(:first)</tt>. - def first(*args) - find(:first, *args) - end - - # A convenience wrapper for <tt>find(:last, *args)</tt>. You can pass in all the - # same arguments to this method as you can to <tt>find(:last)</tt>. - def last(*args) - find(:last, *args) - end - - # A convenience wrapper for <tt>find(:all, *args)</tt>. You can pass in all the - # same arguments to this method as you can to <tt>find(:all)</tt>. - def all(*args) - find(:all, *args) - end - # Executes a custom SQL query against your database and returns all the results. The results will # be returned as an array with columns requested encapsulated as attributes of the model you call # this method from. If you call <tt>Product.find_by_sql</tt> then the results will be returned in |