文章介绍了关于oracle正则函数的一些用法,包括匹配等,Oracle10g提供了在查询中使用正则表达的功能,它是通过各种支持正则表达式的函数在where子句中实现的
文章介绍了关于oracle正则函数的一些用法,包括匹配等,Oracle10g提供了在查询中使用正则表达的功能,它是通过各种支持正则表达式的函数在where子句中实现的ORACLE中的支持正则表达式的函数主要有下面四个:
1,REGEXP_LIKE :与LIKE的功能相似
2,REGEXP_INSTR :与INSTR的功能相似
3,REGEXP_SUBSTR :与SUBSTR的功能相似
4,REGEXP_REPLACE :与REPLACE的功能相似
1、正则表达式中的元字符
元字符 意思 例子
说明要匹配的字符是一个特殊字符、常量或者后者引用。(后引用重复上一次的匹配) n 匹配换行符
\ 匹配
( 匹配 (
) 匹配 )
^ 匹配字符串的开头位置 如果A是字符串的第一个字符,^A 匹配 A
$ 匹配字符串的末尾位置 如果B是字符串的最后一个字符,$B 匹配 B
* 匹配前面的字符0次或多次 ba*rk可以匹配 brk、bark、baark等等
+ 匹配前面的字符1次或多次 ba+rk可以匹配 bark、baark等等,但是不能匹配brk,也就是说,最少有以一次。
? 匹配前面的字符0次或1次 ba?rk可以匹配 bark、brk等等,但是不能匹配baark。
{n} 匹配前面的字符恰好是n次,其中n是整数 hob{2}it可以匹配hobbit
{n,m} 匹配前面的字符至少是n次,最多是m次,其中n,m都是整数 hob{2,3}it可以匹配hobbit或者hobbbit
. 匹配除null以外的任意单个字符 hob.it中的.可以是任意的单个字符,如:hobsit等等
(pattern) 括号中pattern是一个子正则表达式,匹配指定pattern模式的一个子表达式。 如:aaa(x|y)可以匹配aaax或者aaay。
x|y 匹配“或” x|y可以匹配x或者y
[abc] 可以匹配abc中的任何单个字符 hello[abc]可以匹配helloa,hellob,helloc
[a-z] 可以匹配指定范围内的任何单个字符 hell[a-z]可以匹配hello或者hellz
[::] 指定一个字符类,可以匹配该类中的任何字符 [:alphanum:]可以匹配字符0-9、A-Z、a-z
[:alpha:]可以匹配字符A-Z、a-z
[:blank:]可以匹配空格或tab键
[:digit:]可以匹配数字0-9
[:graph:]可以匹配非空字符
[:lower:]可以匹配小写字母a-z
[:print:]与[:graph:]类似,不同之处在于[:print:]包括空格字符
[:punct:]可以匹配标点符号.,""等等
[:space:]可以匹配所有的空字符
[:upper:]可以匹配大写字母A-Z
[:xdigit:]可以匹配十六进制数字0-9、A-F、a-f
n 这是对前一次匹配命中的一个后引用,其中n是一个正整数 (.)1可以匹配两个连续相同的非空字符。(.)可以匹配除null以外的任何单个字符,而1则重复上一次匹配的内容,即再次匹配相同的字符,因此可以匹配两个连续相同的非空字符
2、REGEXP_LIKE(x,pattern[,match_option])用于在x中查找正则表达式pattern,该函数还可以提供一个可选的参数match_option字符串说明默认的匹配选项。match_option的取值如下:
‘c’ 说明在进行匹配时区分大小写(缺省值);
'i' 说明在进行匹配时不区分大小写;
'n' 允许使用可以匹配任意字符的操作符;
'm' 将x作为一个包含多行的字符串。
--测试数据
代码如下 | 复制代码 |
create table test(mc varchar2(60)); insert into test values('112233445566778899'); commit; |
一、REGEXP_LIKE
代码如下 | 复制代码 |
select * from test where regexp_like(mc,'^a{1,3}'); |
二、REGEXP_INSTR
代码如下 | 复制代码 |
Select REGEXP_INSTR(mc,'[[:digit:]]$') from test; |
三、REGEXP_SUBSTR
代码如下 | 复制代码 |
SELECT REGEXP_SUBSTR(mc,'[a-z]+') FROM test; |
四、REGEXP_REPLACE
代码如下 | 复制代码 |
Select REGEXP_REPLACE('Joe Smith','( ){2,}', ',') AS RX_REPLACE FROM dual; SQL> select * from test; ID MC b bbbbb |
SQL> select * from test where regexp_like(id,'b','i'); --不区分数据大小写
ID MC
-------------------- ------------------------------------------------------------
b bbbbb
#End
接下来的几节将会介绍更多有关正则表达式函数的知识。
1. REGEXP_LIKE()
REGEXP_LIKE(x, pattern [, match_option])用于在x中查找pattern参数中定义的正则表达式,该函数还可以提供一个可选参数match_option,它可以设置为下面几个字符之一:
'c',说明在匹配时区分大小写(默认选项)
'I',说明在匹配时不区分大小写
'n',允许使用可以匹配任意字符的操作符
'm',将x 作为一个包含多行的字符串
下面这个查询使用REGEXP_LIKE函数检索生日在1965年到1968年之间的顾客:
代码如下 | 复制代码 |
SELECT customer_id, first_name, last_name, dob FROM customers WHERE REGEXP_LIKE(TO_CHAR(dob, 'YYYY'), '^196[5-8]$');
CUSTOMER_ID FIRST_NAME LAST_NAME DOB ----------- ---------- ---------- --------- 1 John Brown 01-JAN-65 2 Cynthia Green 05-FEB-68 |
下面这个查询检索名字以J或j开头的顾客。注意传递给REGEXP_LIKE()的正则表达式是 ^j,匹配选项是i,这说明不区分大小写,因此在本例中,^j 可以匹配J或j:
代码如下 | 复制代码 |
SELECT customer_id, first_name, last_name, dob FROM customers WHERE REGEXP_LIKE(first_name, '^j', 'i');
CUSTOMER_ID FIRST_NAME LAST_NAME DOB ----------- ---------- ---------- --------- 1 John Brown 01-JAN-65 |
2. REGEXP_INSTR()
REGEXP_INSTR(x, pattern [, start [, occurrence [, return_option [, match_option]]]])用于在x中查找pattern;REGEXP_INSTR()返回pattern出现的位置。匹配位置从1开始。
下面这个查询使用REGEXP_INSTR函数返回匹配正则表达式 l[[:alpha:]]{4}的位置:
代码如下 | 复制代码 |
SELECT REGEXP_INSTR('But, soft! What light through yonder window breaks?', 'l[[:alpha:]]{4}') AS result FROM dual;
RESULT ---------- 17 |
注意返回值为17,这是light中l的位置。
下面这个查询返回第二次匹配正则表达式 s[[:alpha:]]{3}的位置,匹配位置从1开始:
代码如下 | 复制代码 |
SELECT REGEXP_INSTR('But, soft! What light through yonder window softly breaks?', 's[[:alpha:]]{3}', 1, 2) AS result FROM dual;
RESULT ---------- 45 |
下面这个查询使用REGEXP_INSTR函数返回第二次匹配字母 o 的位置,匹配位置从10开始:
代码如下 | 复制代码 |
SELECT REGEXP_INSTR('But, soft! What light through yonder window breaks?', 'o', 10, 2) AS result FROM dual;
RESULT ---------- 32 |
3. REGEXP_REPLACE()
REGEXP_REPLACE(x, pattern [, replace_string [, start [, occurrence[, match_option]]]])用于在x中查找pattern,并将其替换为 replace_string。
下面这个查询使用REGEXP_REPLACE函数将匹配正则表达式 l[[:alpha:]]{4}的子字符串替换为字符串 sound:
代码如下 | 复制代码 |
SELECT REGEXP_REPLACE('But, soft! What light through yonder window breaks?', 'l[[:alpha:]]{4}', 'sound') AS result FROM dual;
RESULT |
---------------------------------------------------
But, soft! What sound through yonder window breaks?
注意light已经被替换为sound。
4. REGEXP_SUBSTR()
REGEXP_SUBSTR(x, pattern[, start [, occurrence[, match_option]]])用于在x中查找匹配pattern的子字符串,开始位置由 start指定。
下面这个查询使用REGEXP_SUBSTR函数返回匹配正则表达式 l[[:alpha:]]{4}的子字符串:
代码如下 | 复制代码 |
SELECT REGEXP_SUBSTR('But, soft! What light through yonder window breaks?', 'l[[:alpha:]]{4}') AS result FROM dual;
RESUL ----- light |
5. REGEXP_COUNT()
REGEXP_COUNT()是Oracle Database11g新增加的一个函数。REGEXP_COUNT(x, pattern[, start [,match_option]])用于在x中查找pattern,并返回pattern在x中出现的次数。可以提供可选参数start,指出要从x中开始查找pattern的那个字符;也可以提供可选的match_option字符串,指出匹配选项。
下面这个查询使用REGEXP_COUNT函数返回正则表达式s[[:alpha:]]{3}出现的次数:
代码如下 | 复制代码 |
SELECT REGEXP_COUNT('But, soft! What light through yonder window softly breaks?', 's[[:alpha:]]{3}') AS result FROM dual;
RESULT ---------- 2 |
注意返回结果是2,这表明正则表达式在提供的字符串中有两次匹配。
•oracle正则表达匹配手机特号
尾号四连号:([0123456789])111$ 如:13498212222、13613431111
sql:select * from tb_phone where REGEXP_LIKE(phone_no,'([0123456789])111$')
尾号四连顺:(0123|1234|2345|3456|4567|5678|6789)$ 如:13576531234、13623432345
尾号倒四连顺:(9876|8765|7654|6543|5432|4321|3210)$ 如:13512329876、13676987654
尾号00XX:00[[:digit:]][[:digit:]]$ 如:13512320023、13512320035
尾号AABB:([[:digit:]])1([[:digit:]])2$ 如:13567545566
尾号ABAB:([[:digit:]]{2})1$ 如:13545341212
尾号AAAB:([[:digit:]])11[[:digit:]]$ 如:13564326667

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