49 lines
1.6 KiB
Markdown
49 lines
1.6 KiB
Markdown
---
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title: SQL Between Operator
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localeTitle: 运算符之间的SQL
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---
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## 运算符之间的SQL
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由于SQL查询优化器，BETWEEN运算符很有用。虽然BETWEEN在功能上与以下相同： x <= element <= y，SQL查询优化器将更快地识别此命令，并具有用于运行它的优化代码。
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此运算符用于WHERE子句或GROUP BY HAVING子句中。
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选择的行的值大于最小值且小于最大值。
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请务必记住，命令中输入的值将从结果中**排除** 。我们得到它们之间的东西。
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以下是在WHERE子句中使用该函数的语法：
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```sql
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select field1, testField
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from table1
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where testField between min and max
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```
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以下是使用student表和WHERE子句的示例：
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```sql
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-- no WHERE clause
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select studentID, FullName, studentID
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from student;
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-- WHERE clause with between
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select studentID, FullName, studentID
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from student
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where studentID between 2 and 7;
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```
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以下是使用广告系列基金表和having子句的示例。 这将返回行，其中候选人的捐款总额在300万美元到1800万美元之间，基于声明的GROUP BY部分中的HAVING子句。更多关于该指南中的汇总。
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```sql
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select Candidate, Office_Sought, Election_Year, format(sum(Total_$),2)
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from combined_party_data
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where Election_Year = 2016
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group by Candidate, Office_Sought, Election_Year
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having sum(Total_$) between 3000000 and 18000000
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order by sum(Total_$) desc;
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```
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