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class ActiveRecord::ConnectionAdapters::SchemaCache

Parent:
Object

Attributes

connection[RW]
version[R]

Public Class Methods

new(conn) Show source
# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 9
def initialize(conn)
  @connection = conn

  @columns      = {}
  @columns_hash = {}
  @primary_keys = {}
  @data_sources = {}
end

Public Instance Methods

add(table_name) Show source
# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 55
def add(table_name)
  if data_source_exists?(table_name)
    primary_keys(table_name)
    columns(table_name)
    columns_hash(table_name)
  end
end

Add internal cache for table with table_name.

clear!() Show source
# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 81
def clear!
  @columns.clear
  @columns_hash.clear
  @primary_keys.clear
  @data_sources.clear
  @version = nil
end

Clears out internal caches

clear_data_source_cache!(name) Show source
# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 94
def clear_data_source_cache!(name)
  @columns.delete name
  @columns_hash.delete name
  @primary_keys.delete name
  @data_sources.delete name
end

Clear out internal caches for the data source name.

columns(table_name) Show source
# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 68
def columns(table_name)
  @columns[table_name] ||= connection.columns(table_name)
end

Get the columns for a table

columns_hash(table_name) Show source
# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 74
def columns_hash(table_name)
  @columns_hash[table_name] ||= Hash[columns(table_name).map { |col|
    [col.name, col]
  }]
end

Get the columns for a table as a hash, key is the column name value is the column object.

data_source_exists?(name) Show source
# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 47
def data_source_exists?(name)
  prepare_data_sources if @data_sources.empty?
  return @data_sources[name] if @data_sources.key? name

  @data_sources[name] = connection.data_source_exists?(name)
end

A cached lookup for table existence.

data_sources(name) Show source
# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 63
def data_sources(name)
  @data_sources[name]
end
encode_with(coder) Show source
# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 26
def encode_with(coder)
  coder["columns"] = @columns
  coder["columns_hash"] = @columns_hash
  coder["primary_keys"] = @primary_keys
  coder["data_sources"] = @data_sources
  coder["version"] = connection.migration_context.current_version
end
init_with(coder) Show source
# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 34
def init_with(coder)
  @columns = coder["columns"]
  @columns_hash = coder["columns_hash"]
  @primary_keys = coder["primary_keys"]
  @data_sources = coder["data_sources"]
  @version = coder["version"]
end
initialize_dup(other) Show source
# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 18
def initialize_dup(other)
  super
  @columns      = @columns.dup
  @columns_hash = @columns_hash.dup
  @primary_keys = @primary_keys.dup
  @data_sources = @data_sources.dup
end
Calls superclass method
marshal_dump() Show source
# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 101
def marshal_dump
  # if we get current version during initialization, it happens stack over flow.
  @version = connection.migration_context.current_version
  [@version, @columns, @columns_hash, @primary_keys, @data_sources]
end
marshal_load(array) Show source
# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 107
def marshal_load(array)
  @version, @columns, @columns_hash, @primary_keys, @data_sources = array
end
primary_keys(table_name) Show source
# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 42
def primary_keys(table_name)
  @primary_keys[table_name] ||= data_source_exists?(table_name) ? connection.primary_key(table_name) : nil
end
size() Show source
# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 89
def size
  [@columns, @columns_hash, @primary_keys, @data_sources].map(&:size).inject :+
end

© 2004–2018 David Heinemeier Hansson
Licensed under the MIT License.