25 lines
576 B
Markdown
25 lines
576 B
Markdown
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---
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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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“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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以下是使用该函数的语法：
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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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以下是使用学生表的示例：
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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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