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mysql正则表达式regexp使用详解

Jun 07, 2016 pm 04:38 PM
mysql regexp use regular expression Detailed explanation

regexp ^??????????????? ???????? 匹配字符串的开始部分 $??????????????? ???????? 匹配字符串的结束部分 .???????????????? ???????? 匹配任何字符(包括回车和新行) a*????????????? ???????? 匹配0或多个a字符的任何序列 a+????????????? ???????? 匹

regexp

^??????????????? ???????? 匹配字符串的开始部分

$??????????????? ???????? 匹配字符串的结束部分

.???????????????? ???????? 匹配任何字符(包括回车和新行)

a*????????????? ???????? 匹配0或多个a字符的任何序列

a+????????????? ???????? 匹配1个或多个a字符的任何序列

a?????????????? ???????? 匹配0个或1个a字符

de|abc?????????????? 匹配序列de或abc

(abc)*??????????????? 匹配序列adc的0个或者多个实例

{n}、{m,n}??????? {n}或{m,n}符号提供了编写正则表达式的更通用方式,能够匹配模式的很多前述原子(或“部分”)。m和n均为整数。

a*????????????? 可被写为a{0,}

a+????????????? 可被写为a{1,}

a?????????????? 可被写为a{0,1}

[a-dX]???????????????? 匹配任何是a,b,c,d或者X的字符,两个其他字符之间的’-'字符构成一个范围

[^a-dX]?????????????? 匹配任何不是a,b,c,d或者X的字符,前面的字符’^'是否定的意思

[.characters.]? 在括号表达式中(使用[和]),匹配用于校对元素的字符序列,字符为单个字符或新行等字符名

mysql> SELECT ‘~’ REGEXP ‘[[.~.]]’; ?????????????????????????????????????????????????????? -> 1

mysql> SELECT ‘~’ REGEXP ‘[[.tilde.]]’; ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? -> 1

[=character_class=]

在括号表达式中(使用[和]),[=character_class=]表示等同类。它与具有相同校对值的所有字符匹配,包括它本身,

[[=a=]] ???????????? 等同于[a(+)],[a+],[a{1,}]

[:character_class:]

在括号表达式中(使用[和]),[:character_class:]表示与术语类的所有字符匹配的字符类。

标准的类名称是:

alnum?????? 文字数字字符

alpha??????? 文字字符

blank???????? 空白字符

cntrl ???????? 控制字符

digit????????? 数字字符

graph??????? 图形字符

lower??????? 小写文字字符

print ? ? ? ? ?图形或空格字符

punct??????? 标点字符

space??????? 空格、制表符、新行、和回车

upper??????? 大写文字字符

xdigit??????? 十六进制数字字符

[[:<:>:]]

这些标记表示word边界。它们分别与word的开始和结束匹配。word是一系列字字符,其前面和后面均没有字字符。字符是alnum类中的字母数字字符或下划线(_)。

mysql> select ‘fang shan zi’ regexp ‘[[:<:>:]]’;???????????? -> 1

mysql> select ‘fang shan zi’ regexp ‘[[:<:>:]]’;????????????? -> 1

mysql> select ‘fang shans zi’ regexp ‘[[:<:>:]]’;?????????? -> 0

正则表达式使用特殊字符,应在其前面加上2个反斜杠’\'字符

mysql> SELECT ’1+2′ REGEXP ’1+2′;?????????????????????? -> 0

mysql> SELECT ’1+2′ REGEXP ’1\+2′;????????????????????? -> 0

mysql> SELECT ’1+2′ REGEXP ’1\\+2′;???????????????????? -> 1

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