59 lines
		
	
	
		
			1.4 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			59 lines
		
	
	
		
			1.4 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
--echo #
 | 
						|
--echo # Try DENSE_RANK() function
 | 
						|
--echo #
 | 
						|
 | 
						|
create table t1 (
 | 
						|
  pk int primary key,
 | 
						|
  a int,
 | 
						|
  b int
 | 
						|
);
 | 
						|
 | 
						|
insert into t1 values
 | 
						|
( 1 , 0, 10),
 | 
						|
( 2 , 0, 10),
 | 
						|
( 3 , 1, 10),
 | 
						|
( 4 , 1, 10),
 | 
						|
( 8 , 2, 10),
 | 
						|
( 5 , 2, 20),
 | 
						|
( 6 , 2, 20),
 | 
						|
( 7 , 2, 20),
 | 
						|
( 9 , 4, 20),
 | 
						|
(10 , 4, 20);
 | 
						|
 | 
						|
select pk, a, b, rank() over (order by a) as rank,
 | 
						|
                 dense_rank() over (order by a) as dense_rank
 | 
						|
from t1;
 | 
						|
select pk, a, b, rank() over (partition by b order by a) as rank,
 | 
						|
                 dense_rank() over (partition by b order by a) as dense_rank
 | 
						|
from t1;
 | 
						|
 | 
						|
drop table t1;
 | 
						|
 | 
						|
--echo #
 | 
						|
--echo # Test with null values in the table.
 | 
						|
--echo #
 | 
						|
 | 
						|
create table t2 (s1 int, s2 char(5));
 | 
						|
insert into t2 values (1,'a');
 | 
						|
insert into t2 values (null,null);
 | 
						|
insert into t2 values (1,null);
 | 
						|
insert into t2 values (null,'a');
 | 
						|
insert into t2 values (null,'c');
 | 
						|
insert into t2 values (2,'b');
 | 
						|
insert into t2 values (-1,'');
 | 
						|
 | 
						|
select *, rank() over (order by s1) as rank,
 | 
						|
          dense_rank() over (order by s1) as dense_rank
 | 
						|
from t2;
 | 
						|
select *, rank() over (partition by s2 order by s1) as rank,
 | 
						|
          dense_rank() over (partition by s2 order by s1) as dense_rank
 | 
						|
from t2;
 | 
						|
select *, rank() over (order by s2) as rank,
 | 
						|
          dense_rank() over (order by s2) as dense_rank
 | 
						|
from t2;
 | 
						|
select *, rank() over (partition by s1 order by s2) as rank,
 | 
						|
          dense_rank() over (partition by s1 order by s2) as dense_rank
 | 
						|
from t2;
 | 
						|
 | 
						|
drop table t2;
 |