MySQL: question about SELECT WHERE AND / OR

Question

I'm trying to write a query that returns the same result from three different events, but I think I'm doing it wrong. I can run my request with a single event id and it works. How can I choose all three? Here is what I still have:

SELECT * FROM `Registrations` WHERE `Role` = "Attendee" AND `RegistrationStatus_ID` = "1" AND `DigSignature` IS NULL AND `Event_ID` = "147" OR `Event_ID` = "155" OR `Event_ID` = "160" 

Answer 1

 SELECT * FROM `Registrations` WHERE `Role` = "Attendee" AND `RegistrationStatus_ID` = "1" AND `DigSignature` IS NULL AND `Event_ID` in ("147", "155", "160") 

Answer 2

 SELECT * FROM `Registrations` WHERE `Role` = "Attendee" AND `RegistrationStatus_ID` = "1" AND `DigSignature` IS NULL AND (`Event_ID` = "147" OR `Event_ID` = "155" OR `Event_ID` = "160") 

When you mix AND and OR, it is useful to use parens to group things together. Even when this is not necessary for logic, it is sometimes useful for others to understand your intentions.

Answer 3

AND and OR have the same priority.

 SELECT * FROM `Registrations` WHERE `Role` = "Attendee" AND `RegistrationStatus_ID` = "1" AND `DigSignature` IS NULL AND (`Event_ID` = "147" OR `Event_ID` = "155" OR `Event_ID` = "160") 

Answer 4

In parentheses you need to enclose the OR operators:

 SELECT * FROM `Registrations` WHERE `Role` = "Attendee" AND `RegistrationStatus_ID` = "1" AND `DigSignature` IS NULL AND (`Event_ID` = "147" OR `Event_ID` = "155" OR `Event_ID` = "160")