資料庫內雖然儲存密碼的欄位是“ password_digest ”，但是實際要把它的欄位名稱當成“ password ”來使用。 2.1.2 :001 > user = User.find_by username: "BBB" User Load (0.6ms) SELECT "users".* FROM "users" WHERE "users"."username" = 'BBB' LIMIT 1 => # 2.1.2 :002 > exit kuruwateki-MacBook-Air:postit-solution shawnkuo67$ rails c Loading development environment (Rails 4.0.0) 2.1.2 :001 > user = User.find_by username: "BBB" User Load (0.7ms) SELECT "users".* FROM "users" WHERE "users"."username" = 'BBB' LIMIT 1 => # 2.1.2 :002 > user. password = 'abcdef' => "abcdef" 2.1.2 :003 > user.save (0.2ms) begin transaction Binary data inserted for `string` type on column ` password_digest ` SQL (6.0ms) UPDATE "users" SET "password_digest" = ?, "updated_at" = ? WHERE "users"."id" = 2 [[...