How to use group by and order by together in sql-SQL-php.cn

How to use group by and order by together in sql

下次还敢

Release： 2024-05-02 03:09:16

Original

975 people have browsed it

Use GROUP BY and ORDER BY to sort grouped data: 1. GROUP BY grouped data; 2. ORDER BY sorts each group of data.

How to use group by and order by together in sql

Combined use of GROUP BY and ORDER BY in SQL

In SQL, both GROUP BY and ORDER BY are important query clauses that can be used to group and sort data sets. You can use both clauses when you want to sort grouped data.

Syntax

<code class="sql">SELECT column_list
FROM table_name
GROUP BY group_column
ORDER BY order_column;</code>

Copy after login

Usage

##1. Grouping

GROUP BY clause is used to group data into specified columns. It combines records with the same grouping column value to form groups.

2. Sorting

The ORDER BY clause is used to sort the data in each group. It sorts the records within a group by a specified sorting column.

Example

For example, we have a table containing student scores:

<code class="sql">CREATE TABLE students (
  student_id INT,
  course_name VARCHAR(255),
  score INT
);</code>

Copy after login

We want to list each student in descending order of their scores Grades for:

<code class="sql">SELECT student_id, course_name, score
FROM students
GROUP BY student_id
ORDER BY score DESC;</code>

Copy after login

Results

The results will be grouped by student ID and sorted by score in descending order for each student.

Note

If multiple columns are specified in GROUP BY, ORDER BY can only sort by these columns.
ORDER BY can be applied to aggregated columns, such as SUM(score).

The above is the detailed content of How to use group by and order by together in sql. For more information, please follow other related articles on the PHP Chinese website!