29 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			SQL
		
	
	
	
	
	
			
		
		
	
	
			29 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			SQL
		
	
	
	
	
	
| ## 
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| # distinct 下压(有才limit 下压)
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| select c1 from t1 union select c2 from t2;
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| # 下压
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| select c1 from t1 union select c2 from t2 limit 2;
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| select c1 from t1 minus select c2 from t2 limit 2;
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| select c1 from t1 limit 2 union select c2 from t2;
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| 
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| # limit 下压(只有union all下压)
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| select c1 from t1 union all select c2 from t2 limit 2;
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| select c1 from t1 limit 5 union all select c2 from t2 limit 2;
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| select c1 from t1 intersect select c2 from t2 limit 2;
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| 
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| # order by 下压
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| select c1 from t1 union all select c2 from t2 order by c1;
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| select c1 from t1 union all select c2 from t2 order by c1 limit 2;
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| select c1, c2 from t1 order by c2 union all select c1, c2 from t2 order by c1 limit 2;
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| select c1, c2 from t1 limit 5 union all select c1, c2 from t2 order by c1 limit 2;
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| select c1 from t1 minus select c2 from t2 order by c1 limit 2;
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| 
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| ## complex test
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| select * from v limit 10 union select * from v limit 10 union select * from v limit 10 union select * from v limit 10 union select * from v limit 10 union select * from v order by c1 limit 10;
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| 
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| select * from v order by c1 union select * from v order by c1 union select * from v order by c1 union select * from v order by c1 union select * from v order by c1 union select * from v order by c1 limit 10;
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| 
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| select * from v order by c1 union all select * from v order by c1 union all select * from v order by c1 union all select * from v order by c1 union all select * from v order by c1 union select * from v order by c1 limit 10;
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| 
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| (select c2 from t1 order by c2 intersect select * from v order by c2 limit 10)union (select c1 from t1 minus select * from v order by c1 limit 11) order by c2 limit 3;
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