Question

I have a contact table I wish to query when a certain condition exists. I tried the query below but am getting a syntax error.

SELECT * 
FROM   contact_details 
WHERE  contactDeleted` =0 
AND    IF ( contactVisibility = "private"
           ,  SELECT * FROM contact_details
              WHERE    contactUserId = 1 
           , IF( contactVisibility = "group"
                ,  SELECT * FROM contact_details  
                   WHERE contactGroup = 3 
               ) 
          )

Answer 1

If I’m understanding your question correctly (which is difficult with the lack of info you’ve provided. Sample datasets and expected outcomes are typically helpful), then I don’t believe you need IFs at all for what you want. The following will return contacts that are not deleted and who either have (visibility = “private” and userId = 1) OR (visibility = “group” and group = 3)

SELECT * 
FROM contact_details 
WHERE contactDeleted = 0 
    AND ( 
        (contactVisibility = "public") 
        OR
        (contactVisibility = "private" AND contactUserId = 1) 
        OR 
        (contactVisibility = "group" AND contactGroup = 3)
    )