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