Top 10 Rows from MySQL A Quick Guide to Retrieving Data(mysql前十条数据)

MySQL is one of the most nearly indispensable tools for developers. Using SQL queries, developers can interact with their databases and write applications that can provide useful insights.

Retrieving data from your MySQL database is one of the most common tasks in web development. By understanding a few basics, you can easily write SQL statements to return the data you need. Here, I will be giving a brief overview on retrieving top 10 rows from MySQL with examples.

To retrieve the top 10 rows, you have to use the “ORDER BY” clause. Using this clause you can order the results in ascending or descending order.

For example, to retrieve the top 10 students by highest points, your query would look something like this

“`sql

SELECT * FROM students

ORDER BY points DESC

LIMIT 10;


In this query, we are first selecting all records from the table. Then, we are ordering the results in descending order i.e. highest points first. Lastly, we are limiting the results to 10.

Thequery above relies on the fact that your table contains a column named points. If you don’t already have such a column, you can always add it by creating a derived column. This is a column generated from one or more columns in the table. For example, the following querycreates a derived column named points_sum which is the total points of each row.

```sql
SELECT
*,
points_1 + points_2 + points_3 AS points_sum
FROM
students;

Once this query has been run, the results can be ordered using the points_sum column

“`sql

SELECT

*,

points_1 + points_2 + points_3 AS points_sum

FROM

students

ORDER BY

points_sum DESC

LIMIT 10;


Retrieving top 10 rows from MySQL can be easily accomplished by using the ORDER BY clause and the LIMIT clause. Once you understand the basics, it’s as easy as writing a few lines of SQL code.

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