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  • mysql 数据操作 单表查询 查询排序: order by

    如果不指定排序 默认是按照id字段 从小到大排序的  升序

    mysql> select * from employee;
    +----+------------+--------+-----+------------+-----------+--------------+------------+--------+-----------+
    | id | name       | sex    | age | hire_date  | post      | post_comment | salary     | office | depart_id |
    +----+------------+--------+-----+------------+-----------+--------------+------------+--------+-----------+
    |  1 | alex       | male   |  78 | 2015-03-02 | teacher   | NULL         | 1000000.31 |    401 |         1 |
    |  2 | yuanhao    | male   |  73 | 2014-07-01 | teacher   | NULL         |    3500.00 |    401 |         1 |
    |  3 | liwenzhou  | male   |  28 | 2012-11-01 | teacher   | NULL         |    2100.00 |    401 |         1 |
    |  4 | jingliyang | female |  18 | 2011-02-11 | teacher   | NULL         |    9000.00 |    401 |         1 |
    |  5 | jinxin     | male   |  18 | 1900-03-01 | teacher   | NULL         |   30000.00 |    401 |         1 |
    |  6 | 成龙       | male   |  48 | 2010-11-11 | teacher   | NULL         |   10000.00 |    401 |         1 |
    |  7 | 歪歪       | female |  48 | 2015-03-11 | sale      | NULL         |    3000.13 |    402 |         2 |
    |  8 | 丫丫       | female |  38 | 2010-11-01 | sale      | NULL         |    2000.35 |    402 |         2 |
    |  9 | 丁丁       | female |  18 | 2011-03-12 | sale      | NULL         |    1000.37 |    402 |         2 |
    | 10 | 星星       | female |  18 | 2016-05-13 | sale      | NULL         |    3000.29 |    402 |         2 |
    | 11 | 格格       | female |  28 | 2017-01-27 | sale      | NULL         |    4000.33 |    402 |         2 |
    | 12 | 张野       | male   |  28 | 2016-03-11 | operation | NULL         |   10000.13 |    403 |         3 |
    | 13 | 程咬金     | male   |  18 | 1997-03-12 | operation | NULL         |   20000.00 |    403 |         3 |
    | 14 | 程咬银     | female |  18 | 2013-03-11 | operation | NULL         |   19000.00 |    403 |         3 |
    | 15 | 程咬铜     | male   |  18 | 2015-04-11 | operation | NULL         |   18000.00 |    403 |         3 |
    | 16 | 程咬铁     | female |  18 | 2014-05-12 | operation | NULL         |   17000.00 |    403 |         3 |
    +----+------------+--------+-----+------------+-----------+--------------+------------+--------+-----------+
    16 rows in set (0.10 sec)

    order by  不指定 asc 默认就是升序

    需求 按照年龄从小到大 排序 升序

    asc 是升序

    mysql> select * from employee order by age asc;
    +----+------------+--------+-----+------------+-----------+--------------+------------+--------+-----------+
    | id | name       | sex    | age | hire_date  | post      | post_comment | salary     | office | depart_id |
    +----+------------+--------+-----+------------+-----------+--------------+------------+--------+-----------+
    | 16 | 程咬铁     | female |  18 | 2014-05-12 | operation | NULL         |   17000.00 |    403 |         3 |
    | 15 | 程咬铜     | male   |  18 | 2015-04-11 | operation | NULL         |   18000.00 |    403 |         3 |
    | 14 | 程咬银     | female |  18 | 2013-03-11 | operation | NULL         |   19000.00 |    403 |         3 |
    | 13 | 程咬金     | male   |  18 | 1997-03-12 | operation | NULL         |   20000.00 |    403 |         3 |
    | 10 | 星星       | female |  18 | 2016-05-13 | sale      | NULL         |    3000.29 |    402 |         2 |
    |  9 | 丁丁       | female |  18 | 2011-03-12 | sale      | NULL         |    1000.37 |    402 |         2 |
    |  5 | jinxin     | male   |  18 | 1900-03-01 | teacher   | NULL         |   30000.00 |    401 |         1 |
    |  4 | jingliyang | female |  18 | 2011-02-11 | teacher   | NULL         |    9000.00 |    401 |         1 |
    | 12 | 张野       | male   |  28 | 2016-03-11 | operation | NULL         |   10000.13 |    403 |         3 |
    |  3 | liwenzhou  | male   |  28 | 2012-11-01 | teacher   | NULL         |    2100.00 |    401 |         1 |
    | 11 | 格格       | female |  28 | 2017-01-27 | sale      | NULL         |    4000.33 |    402 |         2 |
    |  8 | 丫丫       | female |  38 | 2010-11-01 | sale      | NULL         |    2000.35 |    402 |         2 |
    |  7 | 歪歪       | female |  48 | 2015-03-11 | sale      | NULL         |    3000.13 |    402 |         2 |
    |  6 | 成龙       | male   |  48 | 2010-11-11 | teacher   | NULL         |   10000.00 |    401 |         1 |
    |  2 | yuanhao    | male   |  73 | 2014-07-01 | teacher   | NULL         |    3500.00 |    401 |         1 |
    |  1 | alex       | male   |  78 | 2015-03-02 | teacher   | NULL         | 1000000.31 |    401 |         1 |
    +----+------------+--------+-----+------------+-----------+--------------+------------+--------+-----------+
    16 rows in set (0.00 sec)

    不加asc

    mysql> select * from employee order by age ;
    +----+------------+--------+-----+------------+-----------+--------------+------------+--------+-----------+
    | id | name       | sex    | age | hire_date  | post      | post_comment | salary     | office | depart_id |
    +----+------------+--------+-----+------------+-----------+--------------+------------+--------+-----------+
    | 16 | 程咬铁     | female |  18 | 2014-05-12 | operation | NULL         |   17000.00 |    403 |         3 |
    | 15 | 程咬铜     | male   |  18 | 2015-04-11 | operation | NULL         |   18000.00 |    403 |         3 |
    | 14 | 程咬银     | female |  18 | 2013-03-11 | operation | NULL         |   19000.00 |    403 |         3 |
    | 13 | 程咬金     | male   |  18 | 1997-03-12 | operation | NULL         |   20000.00 |    403 |         3 |
    | 10 | 星星       | female |  18 | 2016-05-13 | sale      | NULL         |    3000.29 |    402 |         2 |
    |  9 | 丁丁       | female |  18 | 2011-03-12 | sale      | NULL         |    1000.37 |    402 |         2 |
    |  5 | jinxin     | male   |  18 | 1900-03-01 | teacher   | NULL         |   30000.00 |    401 |         1 |
    |  4 | jingliyang | female |  18 | 2011-02-11 | teacher   | NULL         |    9000.00 |    401 |         1 |
    | 12 | 张野       | male   |  28 | 2016-03-11 | operation | NULL         |   10000.13 |    403 |         3 |
    |  3 | liwenzhou  | male   |  28 | 2012-11-01 | teacher   | NULL         |    2100.00 |    401 |         1 |
    | 11 | 格格       | female |  28 | 2017-01-27 | sale      | NULL         |    4000.33 |    402 |         2 |
    |  8 | 丫丫       | female |  38 | 2010-11-01 | sale      | NULL         |    2000.35 |    402 |         2 |
    |  7 | 歪歪       | female |  48 | 2015-03-11 | sale      | NULL         |    3000.13 |    402 |         2 |
    |  6 | 成龙       | male   |  48 | 2010-11-11 | teacher   | NULL         |   10000.00 |    401 |         1 |
    |  2 | yuanhao    | male   |  73 | 2014-07-01 | teacher   | NULL         |    3500.00 |    401 |         1 |
    |  1 | alex       | male   |  78 | 2015-03-02 | teacher   | NULL         | 1000000.31 |    401 |         1 |
    +----+------------+--------+-----+------------+-----------+--------------+------------+--------+-----------+
    16 rows in set (0.00 sec)

    降序 desc

    mysql> select * from employee order by age desc;
    +----+------------+--------+-----+------------+-----------+--------------+------------+--------+-----------+
    | id | name       | sex    | age | hire_date  | post      | post_comment | salary     | office | depart_id |
    +----+------------+--------+-----+------------+-----------+--------------+------------+--------+-----------+
    |  1 | alex       | male   |  78 | 2015-03-02 | teacher   | NULL         | 1000000.31 |    401 |         1 |
    |  2 | yuanhao    | male   |  73 | 2014-07-01 | teacher   | NULL         |    3500.00 |    401 |         1 |
    |  7 | 歪歪       | female |  48 | 2015-03-11 | sale      | NULL         |    3000.13 |    402 |         2 |
    |  6 | 成龙       | male   |  48 | 2010-11-11 | teacher   | NULL         |   10000.00 |    401 |         1 |
    |  8 | 丫丫       | female |  38 | 2010-11-01 | sale      | NULL         |    2000.35 |    402 |         2 |
    |  3 | liwenzhou  | male   |  28 | 2012-11-01 | teacher   | NULL         |    2100.00 |    401 |         1 |
    | 12 | 张野       | male   |  28 | 2016-03-11 | operation | NULL         |   10000.13 |    403 |         3 |
    | 11 | 格格       | female |  28 | 2017-01-27 | sale      | NULL         |    4000.33 |    402 |         2 |
    | 14 | 程咬银     | female |  18 | 2013-03-11 | operation | NULL         |   19000.00 |    403 |         3 |
    | 15 | 程咬铜     | male   |  18 | 2015-04-11 | operation | NULL         |   18000.00 |    403 |         3 |
    | 13 | 程咬金     | male   |  18 | 1997-03-12 | operation | NULL         |   20000.00 |    403 |         3 |
    | 10 | 星星       | female |  18 | 2016-05-13 | sale      | NULL         |    3000.29 |    402 |         2 |
    |  9 | 丁丁       | female |  18 | 2011-03-12 | sale      | NULL         |    1000.37 |    402 |         2 |
    |  5 | jinxin     | male   |  18 | 1900-03-01 | teacher   | NULL         |   30000.00 |    401 |         1 |
    |  4 | jingliyang | female |  18 | 2011-02-11 | teacher   | NULL         |    9000.00 |    401 |         1 |
    | 16 | 程咬铁     | female |  18 | 2014-05-12 | operation | NULL         |   17000.00 |    403 |         3 |
    +----+------------+--------+-----+------------+-----------+--------------+------------+--------+-----------+
    16 rows in set (0.00 sec)
    按多列排序:先按照age升序 排序,如果年龄age相同情况下,年龄分不出胜负情况下 ,则按照id  降序排序

    mysql> select * from employee order by age asc,id desc;
    +----+------------+--------+-----+------------+-----------+--------------+------------+--------+-----------+
    | id | name       | sex    | age | hire_date  | post      | post_comment | salary     | office | depart_id |
    +----+------------+--------+-----+------------+-----------+--------------+------------+--------+-----------+
    | 16 | 程咬铁     | female |  18 | 2014-05-12 | operation | NULL         |   17000.00 |    403 |         3 |
    | 15 | 程咬铜     | male   |  18 | 2015-04-11 | operation | NULL         |   18000.00 |    403 |         3 |
    | 14 | 程咬银     | female |  18 | 2013-03-11 | operation | NULL         |   19000.00 |    403 |         3 |
    | 13 | 程咬金     | male   |  18 | 1997-03-12 | operation | NULL         |   20000.00 |    403 |         3 |
    | 10 | 星星       | female |  18 | 2016-05-13 | sale      | NULL         |    3000.29 |    402 |         2 |
    |  9 | 丁丁       | female |  18 | 2011-03-12 | sale      | NULL         |    1000.37 |    402 |         2 |
    |  5 | jinxin     | male   |  18 | 1900-03-01 | teacher   | NULL         |   30000.00 |    401 |         1 |
    |  4 | jingliyang | female |  18 | 2011-02-11 | teacher   | NULL         |    9000.00 |    401 |         1 |
    | 12 | 张野       | male   |  28 | 2016-03-11 | operation | NULL         |   10000.13 |    403 |         3 |
    | 11 | 格格       | female |  28 | 2017-01-27 | sale      | NULL         |    4000.33 |    402 |         2 |
    |  3 | liwenzhou  | male   |  28 | 2012-11-01 | teacher   | NULL         |    2100.00 |    401 |         1 |
    |  8 | 丫丫       | female |  38 | 2010-11-01 | sale      | NULL         |    2000.35 |    402 |         2 |
    |  7 | 歪歪       | female |  48 | 2015-03-11 | sale      | NULL         |    3000.13 |    402 |         2 |
    |  6 | 成龙       | male   |  48 | 2010-11-11 | teacher   | NULL         |   10000.00 |    401 |         1 |
    |  2 | yuanhao    | male   |  73 | 2014-07-01 | teacher   | NULL         |    3500.00 |    401 |         1 |
    |  1 | alex       | male   |  78 | 2015-03-02 | teacher   | NULL         | 1000000.31 |    401 |         1 |
    +----+------------+--------+-----+------------+-----------+--------------+------------+--------+-----------+
    16 rows in set (0.00 sec)
    
    
    
     
    按单列排序
        SELECT * FROM employee ORDER BY salary;
        SELECT * FROM employee ORDER BY salary ASC;
        SELECT * FROM employee ORDER BY salary DESC;
    
    按多列排序:先按照age排序,如果年纪相同,则按照薪资排序
        SELECT * from employee
            ORDER BY age,
            salary DESC;
    
    
    
    
    
    1. 查询所有员工信息,先按照age升序排序,如果age相同则按照hire_date降序排序
    select * from employee order by age,hire_date desc;
    +----+------------+--------+-----+------------+-----------+--------------+------------+--------+-----------+
    | id | name       | sex    | age | hire_date  | post      | post_comment | salary     | office | depart_id |
    +----+------------+--------+-----+------------+-----------+--------------+------------+--------+-----------+
    | 10 | 星星       | female |  18 | 2016-05-13 | sale      | NULL         |    3000.29 |    402 |         2 |
    | 15 | 程咬铜     | male   |  18 | 2015-04-11 | operation | NULL         |   18000.00 |    403 |         3 |
    | 16 | 程咬铁     | female |  18 | 2014-05-12 | operation | NULL         |   17000.00 |    403 |         3 |
    | 14 | 程咬银     | female |  18 | 2013-03-11 | operation | NULL         |   19000.00 |    403 |         3 |
    |  9 | 丁丁       | female |  18 | 2011-03-12 | sale      | NULL         |    1000.37 |    402 |         2 |
    |  4 | jingliyang | female |  18 | 2011-02-11 | teacher   | NULL         |    9000.00 |    401 |         1 |
    | 13 | 程咬金     | male   |  18 | 1997-03-12 | operation | NULL         |   20000.00 |    403 |         3 |
    |  5 | jinxin     | male   |  18 | 1900-03-01 | teacher   | NULL         |   30000.00 |    401 |         1 |
    | 11 | 格格       | female |  28 | 2017-01-27 | sale      | NULL         |    4000.33 |    402 |         2 |
    | 12 | 张野       | male   |  28 | 2016-03-11 | operation | NULL         |   10000.13 |    403 |         3 |
    |  3 | liwenzhou  | male   |  28 | 2012-11-01 | teacher   | NULL         |    2100.00 |    401 |         1 |
    |  8 | 丫丫       | female |  38 | 2010-11-01 | sale      | NULL         |    2000.35 |    402 |         2 |
    |  7 | 歪歪       | female |  48 | 2015-03-11 | sale      | NULL         |    3000.13 |    402 |         2 |
    |  6 | 成龙       | male   |  48 | 2010-11-11 | teacher   | NULL         |   10000.00 |    401 |         1 |
    |  2 | yuanhao    | male   |  73 | 2014-07-01 | teacher   | NULL         |    3500.00 |    401 |         1 |
    |  1 | alex       | male   |  78 | 2015-03-02 | teacher   | NULL         | 1000000.31 |    401 |         1 |
    +----+------------+--------+-----+------------+-----------+--------------+------------+--------+-----------+
    16 rows in set (0.00 sec)
     

    2. 查询各岗位平均薪资大于10000的岗位名、平均工资,结果按平均薪资升序排列
    mysql> select post,avg(salary) from employee group by post having avg(salary) >10000 order by avg(salary);
    +-----------+---------------+
    | post      | avg(salary)   |
    +-----------+---------------+
    | operation |  16800.026000 |
    | teacher   | 175766.718333 |
    +-----------+---------------+
    2 rows in set (0.01 sec)
    
    
    
    
    
    3. 查询各岗位平均薪资大于10000的岗位名、平均工资,结果按平均薪资降序排列
    mysql> select post,avg(salary) from employee group by post having avg(salary) >10000 order by avg(salary) desc;
    +-----------+---------------+
    | post      | avg(salary)   |
    +-----------+---------------+
    | teacher   | 175766.718333 |
    | operation |  16800.026000 |
    +-----------+---------------+
    2 rows in set (0.01 sec)
     
     
     
     
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  • 原文地址:https://www.cnblogs.com/mingerlcm/p/9880137.html
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