Detailed example of sorting function field() in MySQL

Preface

In our daily development process, sorting is often used, and sometimes there is such a demand.

For example, you need to sort the query results according to the specific value of a field. As in the following example

The above is a personal information table. Suppose we want to sort it by 'seiki', 'iris', 'xut'. That is, name='seiki','iris','xut' are used for sorting.

What should we do when we encounter such a requirement? In fact, there is a MySQL function that can handle this requirement very conveniently.

That is the field() function

How to use it:

Among them, order by （str，str1，str2，str3，str4……） , str is compared with str1, str2, str3, str4, where str refers to the field name,

Meaning: The field str returns the queried result set in the order of strings str1, str2, str3, str4. If the str field value in the table does not exist in the record of str1, str2, str3, str4, it will be returned at the front of the result set.

Now that we know how to use it, let's implement the above requirements.

First, let’s sort in positive order

Or sort by 'seiki', 'iris', the results are as follows

Now let's sort 'seiki', 'iris' in reverse order

You can see that iris is at the front. Why is that? See the annotation on the picture above!

Well, this function is still very useful

Summarize

The above is the full content of this article. I hope that the content of this article will have certain reference learning value for your study or work. If you have any questions, you can leave a message to communicate. Thank you for your support for 123WORDPRESS.COM.