Can mysql sort by numerical size?

mysql can sort by numerical size. MySQL provides the "ORDER BY" keyword to sort the data in the query results in a certain order; the syntax format is "SELECT field name list FROM data table name ORDER BY field name list ASC|DESC;".

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Data that meets user needs can be queried through conditional query statements , but the queried data is generally displayed in the order in which the data was originally added to the table. In order to make the order of query results meet the user's requirements, MySQL provides the ORDER BY keyword to sort the query results.

In practical applications, it is often necessary to sort the query results. For example, when shopping online, the products can be sorted by price; in the hospital registration system, the order of registration can be sorted, etc.

The ORDER BY keyword is mainly used to sort the data in the query results in a certain order. The syntax format is as follows:

SELECT 字段名列表 FROM 数据表名 ORDER BY 字段名列表 ASC|DESC;

The syntax description is as follows.

• Field name list: Indicates the field names that need to be sorted. If there are multiple fields, separate them with commas.

• ASC|DESC: ASC indicates that the fields are sorted in ascending order; DESC indicates that the fields are sorted in descending order. ASC is the default value.

When using the ORDER BY keyword, you should pay attention to the following aspects:

• The ORDER BY keyword can be followed by a subquery (about the subquery) The tutorial will explain it in detail, just learn it here).

• When there is a null value in the sorted field, ORDER BY will treat the null value as the minimum value.

• ORDER BY When specifying multiple fields for sorting, MySQL will sort from left to right according to the order of the fields.

Example:

The following queries all records of the tb_students_info table and sorts the height field. The SQL statement and running results are as follows .

mysql> SELECT * FROM tb_students_info ORDER BY height;
+----+--------+---------+------+------+--------+------------+
| id | name   | dept_id | age  | sex  | height | login_date |
+----+--------+---------+------+------+--------+------------+
|  2 | Green  |       3 |   23 | F    |    158 | 2016-10-22 |
|  1 | Dany   |       1 |   25 | F    |    160 | 2015-09-10 |
|  4 | Jane   |       1 |   22 | F    |    162 | 2016-12-20 |
|  7 | Lily   |       6 |   22 | F    |    165 | 2016-02-26 |
| 10 | Tom    |       4 |   23 | M    |    165 | 2016-08-05 |
|  8 | Susan  |       4 |   23 | F    |    170 | 2015-10-01 |
|  6 | John   |       2 |   21 | M    |    172 | 2015-11-11 |
|  5 | Jim    |       1 |   24 | M    |    175 | 2016-01-15 |
|  9 | Thomas |       3 |   22 | M    |    178 | 2016-06-07 |
|  3 | Henry  |       2 |   23 | M    |    185 | 2015-05-31 |
+----+--------+---------+------+------+--------+------------+
10 rows in set (0.08 sec)

As you can see from the results, MySQL sorts the data in the height field of the query in ascending order according to the size of the value.

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