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抓紧get新技能吧~
MySQL常用字符串函数
大写转小写 lower()
mysql>selectlower("KFDSKGS");
+------------------+
|lower("KFDSKGS")|
+------------------+
|kfdskgs|
+------------------+
小写转大写 upper()
mysql>selectupper("fdssssssss");
+-------------------+
|upper("fdssssssss")|
+-------------------+
|FDSSSSSSSS|
+-------------------+
字符串的连接 concat()
mysql>selectconcat("My","S","QL");
+--------------------+
|concat("My","S","QL")|
+--------------------+
|MySQL|
+--------------------+
截取字符串 substr() / substring()
mysql>selectsubstring("Helloworld",5);
+-----------------------+
|substring("Helloworld",5)|
+-----------------------+
|oworld|
+-----------------------+
1rowinset(0.07sec)
mysql>selectsubstring("Hhlloworld",5,3);
+-------------------------+
|substring("Hhlloworld",5,3)|
+-------------------------+
|ow|
+-------------------------+
1rowinset(0.07sec)
mysql>selectsubstring("Hhlloworld",-5);
+------------------------+
|substring("Hhlloworld",-5)|
+------------------------+
|world|
+------------------------+
1rowinset(0.08sec)
查看字符串的长度 length() 这里的UTF8 中文是占用两个字节
mysql>selectlength("text");
+-------------+
|length("text")|
+-------------+
|4|
+-------------+
mysql>selectlength("你好");
+--------------+
|length("你好")|
+--------------+
|6|
+--------------+
返回一共有多少个字 char_length() 几个字母就是返回多少
mysql>selectchar_length("text");
+------------------+
|char_length("text")|
+------------------+
|4|
+------------------+
1rowinset(0.07sec)
返回字串第一次出现的位置 instr()
mysql>selectinstr("footer","ter");
+-----------------+
|instr("footer","ter")|
+-----------------+
|4|
+-----------------+
如果不够指定的位数则做什么操作 lpad()
mysql>selectlpad("hello",10,"0");
+-----------------+
|lpad("hello",10,"0")|
+-----------------+
|00000hello|
+-----------------+
1rowinset(0.13sec)
位数不够右边补0 rpad()
mysql>selectrpad("hello",10,"0");
+------------------+
|rpad("hello",10,"0")|
+------------------+
|hello00000|
+------------------+
1rowinset(0.13sec)
去除两边的空格 trim()
mysql>selecttrim('bar');
+-------------+
|trim('bar')|
+-------------+
|bar|
+-------------+
1rowinset(0.13sec)
指定字符串截取 左边截取字符串 trim()
mysql>selecttrim(leading'X'from'XXXXXtrimleadingXXXX');
+---------------------------------------+
|trim(leading'X'from'XXXXXtrimleadingXXXX')|
+---------------------------------------+
|trimleadingXXXX|
+---------------------------------------+
1rowinset(0.13sec)
指定去除字符串右边的xyz,左边截取字符串 trim()
mysql>selecttrim(trailing'zyz'from'barxxyz');
+----------------------------+
|trim(trailing'zyz'from'barxxyz')|
+----------------------------+
|barxxyz|
+----------------------------+
1rowinset(0.12sec)
指定去除字符串两边的X trim()
mysql>trim(both'X'from'XXXXXXXtrimbothXXXXXXX')
+----------------------------------------+
|trim(both'X'from'XXXXXXXtrimbothXXXXXXX')|
+----------------------------------------+
|trimboth|
+----------------------------------------+
1rowinset(0.13sec)
替换字符串 replace()
mysql>selectreplace('www.mysql.com','w','W');
+------------------------------+
|replace('www.mysql.com','w','W')|
+------------------------------+
||
+------------------------------+
repeat(str,count) 将字符串str重复count次后返回
mysql>selectrepeat('MySQL',3);
+--------------------+
|repeat('MySQL',3)|
+--------------------+
|MySQLMySQLMySQL|
+--------------------+
1rowinset(0.07sec)
reverse() 将字符串反转后返回
mysql>selectreverse("abcdef");
+-----------------+
|reverse("abcdef")|
+-----------------+
|fedcba|
+-----------------+
1rowinset(0.06sec)
fromat() 科学技术方式
mysql>selectformat(129021,4);
+----------------+
|format(129021,4)|
+----------------+
|129,021.0000|
+----------------+
完结~
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