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Data order by which table its in SQL

开发者 https://www.devze.com 2023-03-11 12:04 出处:网络
So this is a weird one. I have a search for a person that exists in the table \"profile\"and we have people that are allowed to become like a fan of a person.They can favorite them.

So this is a weird one.

I have a search for a person that exists in the table "profile" and we have people that are allowed to become like a fan of a person. They can favorite them.

[Profile]

[uid, first, last, location]

[Favorite]

[A][B]

The profile table consists of some basic information (more than that but thats all that needs to be displayed) and the favorite table consists of 2 unique ids. A has B as a favorite. (A -> B). From the select results i want to display different messages (like this is your friend grou开发者_如何转开发p, this is the other results).

SELECT P.firstname, P.lastname, P.location, P.uid, 2 AS type
FROM profile AS P
    JOIN favorites AS F
    ON F.A = 'myid' and F.B = P.uid
WHERE (P.firstname LIKE 'mich%' or P.lastname LIKE 'mich%')  

So this first one gets all of the people that i consider my favorite. Second, how do i get a general result and append it to SUCH THAT there are no duplicate results?

I tried something like this.

SELECT P.firstname, P.lastname, P.location, P.uid, 2 AS fan
FROM profile AS P
    JOIN favorites AS F
    ON F.A = P.uid and F.B = 'myid'
WHERE (P.firstname LIKE 'micha%' or P.lastname LIKE 'micha%')
  UNION
SELECT P.firstname, P.lastname, P.location, P.uid, 1 AS fan
FROM profile AS P
    JOIN favorites AS F
    ON F.A != P.uid and F.B = 'myid'
WHERE (P.firstname LIKE 'micha%' or P.lastname LIKE 'micha%')


I think you can combine that into one simple query using a case statement and a left join:

select p.firstname, p.lastname, 
   p.location, p.uid, 
   case when f.A is null then 1
   else 2
       end as type
from profile as p
left join favorites as f
 on p.uid = f.B and f.A = 'myid'
where p.firstname like 'mich%' or p.lastname like 'mich%'

This will search profiles for your WHERE clause, and if it matches your favorites join the type field will evaluate to a 2, otherwise it will be one.


I believe this is what you want...

SELECT P.firstname, P.lastname, P.location, P.uid, CASE F.A = P.uid THEN 2 ELSE 1 END AS fan
FROM profile AS P
    LEFT JOIN favorites AS F
    ON  F.B = P.uid
WHERE (P.firstname LIKE 'micha%' or P.lastname LIKE 'micha%')
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