# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 8
def self.load_from(filename)
  return unless File.file?(filename)

  read(filename) do |file|
    if filename.include?(".dump")
      Marshal.load(file)
    else
      if YAML.respond_to?(:unsafe_load)
        YAML.unsafe_load(file)
      else
        YAML.load(file)
      end
    end
  end
end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 38
def initialize(conn)
  @connection = conn

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

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 97
def add(table_name)
  if data_source_exists?(table_name)
    primary_keys(table_name)
    columns(table_name)
    columns_hash(table_name)
    indexes(table_name)
  end
end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 149
def clear!
  @columns.clear
  @columns_hash.clear
  @primary_keys.clear
  @data_sources.clear
  @indexes.clear
  @version = nil
  @database_version = nil
end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 164
def clear_data_source_cache!(name)
  @columns.delete name
  @columns_hash.delete name
  @primary_keys.delete name
  @data_sources.delete name
  @indexes.delete name
end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 111
def columns(table_name)
  if ignored_table?(table_name)
    raise ActiveRecord::StatementInvalid, "Table '#{table_name}' doesn't exist"
  end

  @columns.fetch(table_name) do
    @columns[deep_deduplicate(table_name)] = deep_deduplicate(connection.columns(table_name))
  end
end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 123
def columns_hash(table_name)
  @columns_hash.fetch(table_name) do
    @columns_hash[deep_deduplicate(table_name)] = columns(table_name).index_by(&:name).freeze
  end
end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 130
def columns_hash?(table_name)
  @columns_hash.key?(table_name)
end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 88
def data_source_exists?(name)
  return if ignored_table?(name)
  prepare_data_sources if @data_sources.empty?
  return @data_sources[name] if @data_sources.key? name

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

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 106
def data_sources(name)
  @data_sources[name]
end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 172
def dump_to(filename)
  clear!
  tables_to_cache.each { |table| add(table) }
  open(filename) { |f|
    if filename.include?(".dump")
      f.write(Marshal.dump(self))
    else
      f.write(YAML.dump(self))
    end
  }
end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 57
def encode_with(coder)
  reset_version!

  coder["columns"]          = @columns
  coder["primary_keys"]     = @primary_keys
  coder["data_sources"]     = @data_sources
  coder["indexes"]          = @indexes
  coder["version"]          = @version
  coder["database_version"] = database_version
end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 134
def indexes(table_name)
  @indexes.fetch(table_name) do
    if data_source_exists?(table_name)
      @indexes[deep_deduplicate(table_name)] = deep_deduplicate(connection.indexes(table_name))
    else
      []
    end
  end
end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 68
def init_with(coder)
  @columns          = coder["columns"]
  @primary_keys     = coder["primary_keys"]
  @data_sources     = coder["data_sources"]
  @indexes          = coder["indexes"] || {}
  @version          = coder["version"]
  @database_version = coder["database_version"]

  derive_columns_hash_and_deduplicate_values
end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 48
def initialize_dup(other)
  super
  @columns      = @columns.dup
  @columns_hash = @columns_hash.dup
  @primary_keys = @primary_keys.dup
  @data_sources = @data_sources.dup
  @indexes      = @indexes.dup
end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 184
def marshal_dump
  reset_version!

  [@version, @columns, {}, @primary_keys, @data_sources, @indexes, database_version]
end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 190
def marshal_load(array)
  @version, @columns, _columns_hash, @primary_keys, @data_sources, @indexes, @database_version = array
  @indexes ||= {}

  derive_columns_hash_and_deduplicate_values
end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 79
def primary_keys(table_name)
  @primary_keys.fetch(table_name) do
    if data_source_exists?(table_name)
      @primary_keys[deep_deduplicate(table_name)] = deep_deduplicate(connection.primary_key(table_name))
    end
  end
end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 159
def size
  [@columns, @columns_hash, @primary_keys, @data_sources].sum(&:size)
end