douhan1860 2015-11-03 10:27
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在mySQL中,我希望计算不同县的数量

My Table is as follows

- STUDENT TABLE
- STUDENT NAME    -  COUNTY
- John           -  Waterford
- Chris          -  Waterford
- Anne            - Tipperary
- Paul            - Cork
- Thomas         - Cork

Clearly form the table 3 differrent counties exist, I am looking for a count statement to show that three different counties exist.

Currently I am at

SELECT COUNT(county)
FROM Student;

I have tried Grouping and I can seem to count everything in the table bar the number of counties, any help would be great.

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3条回答 默认 最新

  • douba9425 2015-11-03 10:29
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    use group by

    SELECT county,COUNT(county)
    FROM Student group by county;
    
    本回答被题主选为最佳回答 , 对您是否有帮助呢?
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