如何从一个表中检索所有记录并与当月记录一起

Question

I have 2 tables in my Sqlite database one is USER and other is PAYMENTS

USERS:

ID  Name
"1" "shan"  
"2" "Abc"   
"3" "Def"   
"4" "Whi"

PAYMENTS:

ID  UserID  PayDate         Amount 
"1" "1" "2013-10-27"    "700"
"2" "1" "2013-11-12"    "700"
"3" "2" "2013-09-12"    "800"

How to retrieve all users and those user who paid the amount of the current month. i also want all users who didn't paid yet.

Answer 1

Try somthing like this:

SELECT Users.Name 
FROM Users
LEFT JOIN Payments
  ON Users.ID = Payments.UserID
WHERE Payments.PayDate = <date you are looking for>

You can also use WHERE PayDate BETWEEN 'date1' and 'date2' This should return all users and payment will be NULL if there is no payment record.