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HomeDatabaseMysql TutorialMySQL模糊查询:LIKE模式和REGEXP模式

MySQL模糊查询提供了两种模式:LIKE模式和REGEXP模式。

MySQL模糊查询提供了两种模式:LIKE模式和REGEXP模式。

LIKE模式

LIKE模式是使用的LIKE 或 NOT LIKE 比较运算符进行模糊查询。

'条件'

针对条件,有以下几种通配符:

通配符 含义

% 表示任意一个或多个字符,可匹配任意类型和长度的字符

_ 表示任意单个字符,匹配单个任意字符

ESCAPE 关键字定义转义符。在模式中,当转义符置于通配符之前时,该通配符就解释为普通字符。

 示例:

# 从 "Persons" 表中选取居住在以 "Ne" 开始的城市里的人 Persons # 从 "Persons" 表中选取居住在包含 "lond" 的城市里的人 Persons # 从 "Persons" 表中选取名字的第一个字符之后是 "eorge" 的人 Persons # 从 "Persons" 表中选取的这条记录的姓氏以 "C" 开头,然后是一个任意字符,然后是 "r",然后是任意字符,然后是 "er" Persons # 从 "KPI" 表中查找计算过程中含有0%的指标 KPI

注意:

  • 通配符必须与 LIKE 运算符一起使用
  • 如果没有使用通配符,,LIKE与=是等价的
  • REGEXP模式

    REGEXP模式是使用 REGEXP 操作符来进行正则表达式匹配查询。

    针对条件,有以下几种通配符:

    通配符 含义

    ^ 匹配输入字符串的开始位置。如果设置了 RegExp 对象的 Multiline 属性,^ 也匹配 '\n' 或 '\r' 之后的位置。

    $ 匹配输入字符串的结束位置。如果设置了RegExp 对象的 Multiline 属性,$ 也匹配 '\n' 或 '\r' 之前的位置。

    . 匹配除 "\n" 之外的任何单个字符。要匹配包括 '\n' 在内的任何字符,请使用象 '[.\n]' 的模式。

    [...] 字符集合。匹配所包含的任意一个字符。例如, '[abc]' 可以匹配 "plain" 中的 'a'。

    [^...] 负值字符集合。匹配未包含的任意字符。例如, '[^abc]' 可以匹配 "plain" 中的'p'。

    p1|p2|p3 匹配 p1 或 p2 或 p3。例如,'z|food' 能匹配 "z" 或 "food"。'(z|f)ood' 则匹配 "zood" 或 "food"。

    * 匹配前面的子表达式零次或多次。例如,zo* 能匹配 "z" 以及 "zoo"。* 等价于{0,}。

    + 匹配前面的子表达式一次或多次。例如,'zo+' 能匹配 "zo" 以及 "zoo",但不能匹配 "z"。+ 等价于 {1,}。

    {n} n 是一个非负整数。匹配确定的 n 次。例如,'o{2}' 不能匹配 "Bob" 中的 'o',但是能匹配 "food" 中的两个 o。

    {n,m} m 和 n 均为非负整数,其中n

    示例:

    # 查找name字段中以为开头的所有数据: ; # 查找name字段中以为结尾的所有数据: ; # 查找name字段中包含字符串的所有数据: ; # 查找name字段中以元音字符开头且以字符串结尾的所有数据:

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