substr

description

Syntax

VARCHAR substr(VARCHAR content, INT start, INT length)

求子字符串，返回第一个参数描述的字符串中从start开始长度为len的部分字符串。首字母的下标为1。

example

1. mysql> select substr("Hello doris", 2, 1);
2. +-----------------------------+
3. | substr('Hello doris', 2, 1) |
4. +-----------------------------+
5. | e                           |
6. +-----------------------------+
7. mysql> select substr("Hello doris", 1, 2);
8. +-----------------------------+
9. | substr('Hello doris', 1, 2) |
10. +-----------------------------+
11. | He                          |
12. +-----------------------------+

keywords

1. SUBSTR