Class: ActiveRecord::Result
Relationships & Source Files | |
Super Chains via Extension / Inclusion / Inheritance | |
Instance Chain:
|
|
Inherits: | Object |
Defined in: | activerecord/lib/active_record/result.rb |
Overview
This class encapsulates a result returned from calling #exec_query on any database connection adapter. For example:
result = ActiveRecord::Base.connection.exec_query('SELECT id, title, body FROM posts')
result # => #<ActiveRecord::Result:0xdeadbeef>
# Get the column names of the result:
result.columns
# => ["id", "title", "body"]
# Get the record values of the result:
result.rows
# => [[1, "title_1", "body_1"],
[2, "title_2", "body_2"],
#...
]
# Get an array of hashes representing the result (column => value):
result.to_a
# => [{"id" => 1, "title" => "title_1", "body" => "body_1"},
{"id" => 2, "title" => "title_2", "body" => "body_2"},
#...
]
# ActiveRecord::Result also includes Enumerable.
result.each do |row|
puts row['title'] + " " + row['body']
end
Constant Summary
-
EMPTY =
private
# File 'activerecord/lib/active_record/result.rb', line 195new([].freeze, [].freeze, {}.freeze).freeze
-
EMPTY_ASYNC =
private
# File 'activerecord/lib/active_record/result.rb', line 198FutureResult.wrap(EMPTY).freeze
Class Method Summary
- .new(columns, rows, column_types = {}) ⇒ Result constructor
Instance Attribute Summary
- #column_types readonly
- #columns readonly
-
#empty? ⇒ Boolean
readonly
Returns true if there are no records, otherwise false.
- #rows readonly
::Enumerable
- Included
#many? | Returns |
Instance Method Summary
- #[](idx)
-
#each(&block)
Calls the given block once for each element in row collection, passing row as parameter.
-
#includes_column?(name) ⇒ Boolean
Returns true if this result set includes the column named
name
- #initialize_copy(other)
-
#last(n = nil)
Returns the last record from the rows collection.
-
#length
Returns the number of elements in the rows array.
-
#to_a
Alias for #to_ary.
-
#to_ary
(also: #to_a)
Returns an array of hashes representing each row record.
::Enumerable
- Included
#compact_blank | Returns a new |
#exclude? | The negative of the |
#excluding | Returns a copy of the enumerable excluding the specified elements. |
#in_order_of | Returns a new |
#including | Returns a new array that includes the passed elements. |
#index_by | Convert an enumerable to a hash, using the block result as the key and the element as the value. |
#index_with | Convert an enumerable to a hash, using the element as the key and the block result as the value. |
#maximum | Calculates the maximum from the extracted elements. |
#minimum | Calculates the minimum from the extracted elements. |
#pick | Extract the given key from the first element in the enumerable. |
#pluck | Extract the given key from each element in the enumerable. |
#sole | Returns the sole item in the enumerable. |
#without | Alias for Enumerable#excluding. |
Constructor Details
.new(columns, rows, column_types = {}) ⇒ Result
# File 'activerecord/lib/active_record/result.rb', line 49
def initialize(columns, rows, column_types = {}) @columns = columns @rows = rows @hash_rows = nil @column_types = column_types end
Instance Attribute Details
#column_types (readonly)
[ GitHub ]#columns (readonly)
[ GitHub ]# File 'activerecord/lib/active_record/result.rb', line 39
attr_reader :columns, :rows, :column_types
#empty? ⇒ Boolean
(readonly)
Returns true if there are no records, otherwise false.
# File 'activerecord/lib/active_record/result.rb', line 79
def empty? rows.empty? end
#rows (readonly)
[ GitHub ]# File 'activerecord/lib/active_record/result.rb', line 39
attr_reader :columns, :rows, :column_types
Instance Method Details
#[](idx)
[ GitHub ]# File 'activerecord/lib/active_record/result.rb', line 90
def [](idx) hash_rows[idx] end
#each(&block)
Calls the given block once for each element in row collection, passing row as parameter.
Returns an Enumerator
if no block is given.
# File 'activerecord/lib/active_record/result.rb', line 70
def each(&block) if block_given? hash_rows.each(&block) else hash_rows.to_enum { @rows.size } end end
#includes_column?(name) ⇒ Boolean
Returns true if this result set includes the column named name
# File 'activerecord/lib/active_record/result.rb', line 57
def includes_column?(name) @columns.include? name end
#initialize_copy(other)
[ GitHub ]# File 'activerecord/lib/active_record/result.rb', line 133
def initialize_copy(other) @columns = columns.dup @rows = rows.dup @column_types = column_types.dup @hash_rows = nil end
#last(n = nil)
Returns the last record from the rows collection.
# File 'activerecord/lib/active_record/result.rb', line 95
def last(n = nil) n ? hash_rows.last(n) : hash_rows.last end
#length
Returns the number of elements in the rows array.
# File 'activerecord/lib/active_record/result.rb', line 62
def length @rows.length end
#to_a
Alias for #to_ary.
# File 'activerecord/lib/active_record/result.rb', line 88
alias :to_a :to_ary
#to_ary Also known as: #to_a
Returns an array of hashes representing each row record.
# File 'activerecord/lib/active_record/result.rb', line 84
def to_ary hash_rows end