48 lines
1.5 KiB
Markdown
48 lines
1.5 KiB
Markdown
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---
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title: SQL and Operator
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localeTitle: SQL和运算符
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---
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## SQL AND运算符
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AND在WHERE子句或GROUP BY HAVING子句中用于限制从执行语句返回的行。当需要满足多个条件时使用AND。
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我们将使用student表来展示示例。
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这是没有WHERE子句的student表：
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```sql
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select * from student;
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```
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现在添加了WHERE子句以仅显示编程学生：
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```sql
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select * from student
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where programOfStudy = 'Programming';
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```
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现在，使用AND更新WHERE子句，以显示SAT分数大于800的编程学生的结果：
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```sql
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select * from student
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where programOfStudy = 'Programming'
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and sat_score > 800;
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```
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这是广告系列投稿表中更复杂的示例。此示例具有带有HAVING子句的GROUP BY子句，该子句使用AND将返回的记录限制为2016年的奖金，总额为300万美元到1800万美元。
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```sql
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select Candidate, Office_Sought, Election_Year, FORMAT(sum(Total_$),2) from combined_party_data
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where Office_Sought = 'PRESIDENT / VICE PRESIDENT'
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group by Candidate, Office_Sought, Election_Year
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having Election_Year = 2016 and sum(Total_$) between 3000000 and 18000000
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order by sum(Total_$) desc;
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```
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