如何选择未超过不同列的多个值的记录

Question

I've been looking for a solution for the below question, sadly to no avail. This is for Microsoft SQL Server Management Studio on Microsoft SQL Server.

The database looks more or less like this:

ID    LegID   TripID     
1     0       0  
1     0       1  
1     1       0  
2     0       0  
2     1       0 
2     2       0 
2     2       1  
3     0       0 
3     0       1 
3     0       2

I'm looking for a result where all records will selected be for the ID's where the legID does not exceed 1 and the TripID does not exceed 1. The result then should be:

ID    LegID   TripID     
1     0       0  
1     0       1  
1     1       0

Could you please help me with this?

Answer 1

One method use not exists :

select t.*
from t
where not exists (select 1
                  from t t2
                  where t2.id = t.id and
                        (t2.LegId > 1 or t2.TripId > 1)
                 );

For performance, you want an index on (id, legid, tripid) .

You could also use window functions:

select t.*
from (select t.*,
             max(legid) over (partition by id) as max_legid,
             max(tripid) over (partition by id) as max_tripid
      from t
     ) t
where max_legid <= 1 and max_tripid <= 1;

Answer 2

Use a Derived table (subquery) to get all the id values matching your requirements, utilizing conditional aggregation based filtering. And, then join back to the main table to get all the rows for those id value(s).

SELECT 
  t1.* 
FROM 
  your_table_name t1 
JOIN (SELECT ID
      FROM your_table_name 
      GROUP BY ID 
      HAVING MAX(LegID) <= 1 
         AND MAX(TripID) <= 1) t2 ON t2.ID = t1.ID