Web應用程序如何驗證來自數據庫的數據

Question

我是JEE的新手我想創建一個驗證應用程序，通過servlet驗證postgres數據庫中的登錄名和密碼

Answer 1

I'會形容你的步驟，你將不得不代碼它

1/ get the login info 
2/ do a select inside your database with the user info (select * from table where user = login AND password == password) 
3.1/ if you get 0 result, your user doesn't exist or he doesn't provide the valids information 
3.2/ if you get more than 1 result, you got a problem with your database (maybe your login isn't unique) 
3.3/ if you got only one result, your user exist with this information ! 

當然，你必須有存儲與SHA1 +鹽密碼;）