Detailed example of mysql regular expression (Regexp)
MySQL supports another pattern matching operation based on regular expressions and the REGEXP operator. (Related recommendations: "MySQL Tutorial")
1. It provides powerful and flexible pattern matching, which can help us achieve power for the database system. Search utility.
2.REGEXP is the operator used when performing regular expression pattern matching.
3.RLIKE is a synonym. It also supports a number of metacharacters that provide greater flexibility and control when performing pattern matching.
4. Backslash is used as an escape character. If double backslashes are used, they are only considered in pattern matching.
5. It is not case sensitive.
PATTERN | What does the pattern match? |
* | before it Zero or more string instances |
preceded by one or more string instances | |
. | Any character |
? | matches zero or one instance of the preceding string. |
^ | The caret (^) matches the beginning of the string |
$ | String End |
[abc] | Any characters listed between square brackets |
[^abc] | Any characters not listed between square brackets |
[A-Z] | matches any uppercase letter. |
[a-z] | Matches any lowercase letter |
[0-9] | Matches from Any number from 0 to 9. |
Matches the beginning of a word. | |
Matches the end of a word. | |
matches a character class, that is, [:alpha:] matches letters, [:space:] matches spaces, [:punct:] Matches punctuation, [:upper:] matches upper letters. | |
rotation; matches any pattern p1, p2 or p3 | |
nInstances of the previous element | |
m to n instances of the previous element |
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