Community Learn Tools Library Leisure
search
English
Home > Database > Mysql Tutorial > MySQL创建计算字段――MySQL系列（五）_MySQL

MySQL创建计算字段――MySQL系列（五）_MySQL

WBOY
Release： 2016-06-01 13:17:44
Original
1182 people have browsed it

1、字段

字段与列含义差不多，数据库列一般叫列，字段一般是指计算字段

2、拼接字段

拼接——将值连接到一起构成单个值

Concat()函数

SELECT Concat(name,'(',country,')')AS title FROM companyOrder BY name;
Copy after login
这里的AS title,是取别名，title就是计算字段

3、执行算数计算

可以进行加减乘除的运算

Select prod_num*prod_price，prod_nameFROM products
Copy after login

4、如何测试计算

SELECT 3*2，将返回6

SELECT NOW(),将返回现在时间

Related labels：
Splicing database
source：php.cn
Previous article：mysql的级联操作_MySQL Next article：sql修改字段内容_MySQL
Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
Latest Articles by Author
Latest Issues
Regular expression to match words I have a script where I am trying to match new job names with existing job names in a data...
From 2024-04-06 21:24:04
0
1
606
Calculate the sum of fields in another table using MySQL SQL query I have a schema like this: User table with attributes "user_id" and "userna...
From 2024-04-06 19:39:29
0
1
441
MySQL: "Select text from... as <variable here or subquery>" I have the following table with the following data: id text language 1 german text german ...
From 2024-04-06 19:25:54
0
2
529
MySQL gets data from multiple tables I have a eg_design table which contains the following columns: and eg_domains table which ...
From 2024-04-06 18:42:44
0
2
479
Group MySQL results by ID for looping over I have a table with flight data in mysql. I'm writing a php code that will group and displ...
From 2024-04-06 17:27:56
0
1
406
Related Topics
More>
Popular Recommendations
Popular Tutorials
More>
Related Tutorials
Popular Recommendations
Latest courses
Latest Downloads
More>
Web Effects
Website Source Code
Website Materials
Front End Template