25 lines
		
	
	
		
			576 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			25 lines
		
	
	
		
			576 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
| ---
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| title: SQL Avg Function
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| localeTitle: SQL平均功能
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| ---
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| ## SQL平均(AVG)功能
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| 
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| “Average”是Aggregate(Group By)函数。它用于计算SQL语句返回的行集中的数字列的平均值。
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| 
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| 以下是使用该函数的语法:
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| 
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| ```sql
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| select groupingField, avg(num_field) 
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|  from table1 
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|  group by groupingField 
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| ```
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| 
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| 以下是使用学生表的示例:
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| 
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| ```sql
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| select studentID, FullName, avg(sat_score) 
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|  from student 
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|  group by studentID, FullName; 
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| ```
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| 
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|  |