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mysql常用函数汇总

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Jun 07, 2016 pm 03:13 PM

linuxmysqlfunctionCommonly usedSummaryCommunityEnter

欢迎进入Linux社区论坛，与200万技术人员互动交流 >>进入常见的文本处理函数 Left() 返回串左边的字符 Length() 返回串的长度 Locate() 找出串的一个子串 Lower() 将串转换为小写 LTrim() 去掉串左边的空格 Right() 返回串右边的字符 RTrim() 去掉串右边的

欢迎进入Linux社区论坛，与200万技术人员互动交流 >>进入

常见的文本处理函数

Left() 返回串左边的字符

Length() 返回串的长度

Locate() 找出串的一个子串

Lower() 将串转换为小写

LTrim() 去掉串左边的空格

Right() 返回串右边的字符

RTrim() 去掉串右边的空格

Soundex() 返回串的SOUNDEX值

SubString() 返回子串的字符

SubString_index() 返回子串字符,substring_index(abcdce,c,1)从第一个c前的所有字符,-1就是之后的字符

Upper() 将串转换为大写

日期和时间处理函数

日期格式:yyyy-mm-dd

AddDate() 增加一个日期(天、周等)

AddTime() 增加一个时间(时、分等)

CurDate() 返回当前日期

CurTime() 返回当前时间

Date() 返回日期时间的日期部分

DateDiff() 计算两个日期之差

Date_Add() 高度灵活的日期运算函数

Date_Format() 返回一个格式化的日期或时间串

Day() 返回一个日期的天数部分

DayOfWeek() 返回一个日期,返回对应的星期几

Hour() 返回一个时间的小时部分

Minute() 返回一个时间的分钟部分

Month() 返回一个日期的月份部分

Now() 返回当前日期和时间

Second() 返回一个时间的秒部分

Time() 返回一个日期时间的时间部分

Year() 返回一个日期的年份部分

数值处理函数

Abs() 返回一个数的绝对值

Cos() 返回一个角度的余弦

Exp() 返回一个数的指数值

Mod() 返回除操作的余数

Pi() 返回圆周率

Rand() 返回一个随机数

Sin() 返回一个角度的正弦

Sqrt() 返回一个数的平方根

Tan() 返回一个角度的正切

聚集函数:运行在行组上,计算和返回单个值的函数.

AVG() 返回某列的平均值

COUNT() 返回某列的行数

MAX() 返回某列的最大值

MIN() 返回某列的最小值

SUM() 返回某列值之和

mysql常用函数汇总

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