Shulou(Shulou.com)05/31 Report--

This article mainly explains "MySQL how to duplicate data". Interested friends may wish to have a look. The method introduced in this paper is simple, fast and practical. Let's let Xiaobian take you to learn "MySQL how to re-data"!

The execution result of querying all ages in the tb_students_info table is as follows. When querying data using MySQL SELECT statements, all matching rows are returned.

mysql> SELECT age FROM tb_students_info;+------+| age |+------+| 25 || 23 || 23 || 22 || 24 || 21 || 22 || 23 || 22 || 23 |+------+10 rows in set (0.00 sec)

You can see that the query results returned 10 records, some of which had duplicate age values, and sometimes needed to be eliminated for data analysis purposes. At this time, you need to use the DISTINCT keyword to instruct MySQL to eliminate duplicate record values. The syntax format is:

SELECT DISTINCT FROM ;

Query the value of age field in tb_students_info table, return the value of age field without duplication, input SQL statement and execution result are as follows:

mysql> SELECT DISTINCT age FROM tb_students_info;+------+| age |+------+| 25 || 23 || 22 || 24 || 21 |+------+5 rows in set (0.11 sec)

As can be seen from the running results, the query results only return the age values of 5 records, and there are no duplicate values.

At this point, I believe that everyone has a deeper understanding of "MySQL how to re-data", so let's actually operate it! Here is the website, more related content can enter the relevant channels for inquiry, pay attention to us, continue to learn!

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