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class ActiveRecord::Result

Parent:: Object
Included modules:: Enumerable

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

Attributes

column_types[R]

columns[R]

rows[R]

Public Class Methods

new(columns, rows, column_types = {}) Show source

# File activerecord/lib/active_record/result.rb, line 39
def initialize(columns, rows, column_types = {})
  @columns      = columns
  @rows         = rows
  @hash_rows    = nil
  @column_types = column_types
end

Public Instance Methods

[](idx) Show source

# File activerecord/lib/active_record/result.rb, line 91
def [](idx)
  hash_rows[idx]
end

each() { |row| ... } Show source

# File activerecord/lib/active_record/result.rb, line 60
def each
  if block_given?
    hash_rows.each { |row| yield row }
  else
    hash_rows.to_enum { @rows.size }
  end
end

Calls the given block once for each element in row collection, passing row as parameter.

Returns an Enumerator if no block is given.

empty?() Show source

# File activerecord/lib/active_record/result.rb, line 80
def empty?
  rows.empty?
end

Returns true if there are no records, otherwise false.

first() Show source

# File activerecord/lib/active_record/result.rb, line 97
def first
  return nil if @rows.empty?
  Hash[@columns.zip(@rows.first)]
end

Returns the first record from the rows collection. If the rows collection is empty, returns nil.

includes_column?(name) Show source

# File activerecord/lib/active_record/result.rb, line 47
def includes_column?(name)
  @columns.include? name
end

Returns true if this result set includes the column named name

initialize_copy(other) Show source

# File activerecord/lib/active_record/result.rb, line 127
def initialize_copy(other)
  @columns      = columns.dup
  @rows         = rows.dup
  @column_types = column_types.dup
  @hash_rows    = nil
end

last() Show source

# File activerecord/lib/active_record/result.rb, line 104
def last
  return nil if @rows.empty?
  Hash[@columns.zip(@rows.last)]
end

Returns the last record from the rows collection. If the rows collection is empty, returns nil.

length() Show source

# File activerecord/lib/active_record/result.rb, line 52
def length
  @rows.length
end

Returns the number of elements in the rows array.

to_a()

Alias for: to_ary

to_ary() Show source

# File activerecord/lib/active_record/result.rb, line 85
def to_ary
  hash_rows
end

Returns an array of hashes representing each row record.

Also aliased as: to_a

to_hash() Show source

# File activerecord/lib/active_record/result.rb, line 68
    def to_hash
      ActiveSupport::Deprecation.warn(<<-MSG.squish)
        `ActiveRecord::Result#to_hash` has been renamed to `to_a`.
        `to_hash` is deprecated and will be removed in Rails 6.1.
      MSG
      to_a
    end