Oracle10g正则表达式

Regular expressions in Oracle

With 10g, regular expressions are finally available in SQL. That is, they were already supported through the owa_pattern package.

The new operators and functions are regexp_like, regexp_instr, regexp_substr and regexp_replace

symbol	Matches
.	Any character except newline
^	Start of a line
$	End of a line
*	0, 1, or more of the preceding element. The preceding element can be grouped with ()
{n}	Exactly n repetitions of the preceding element. The preceding element can be grouped with ()
{n,}	Matches n or more repetitions of the preceding element. The preceding element can be grouped with ()
{m,n}	Matches between m and n repetitions of the preceding element. The preceding element can be grouped with ()
[abc]	Character list, matches a, b OR c.
[g-l]	g, h, i, j, k, OR l
|	groups alternatives

Character classes

The following character classes are suppored:

• [[:alnum:]]
  Alphanumeric characters
• [[:alpha:]]
  Alphabetic characters
• [[:blank:]]
  blank space characters
• [[:cntrl:]]
  Control characters
• [[:digit:]]
  0 through 9, or [0-9]
• [[:graph:]]
  [[:punct:]] + [[:upper:]] + [[:lower:]] + [[:digit:]]
• [[:lower:]]
  lowercase alphabetic characters
• [[:print:]]
  Printable characters
• [[:punct:]]
  punctuation characters
• [[:space:]]
  Non-printing space characters
• [[:upper:]]
  Uppercase alphabetic characters
• [[:xdigit:]]
  hexadecimal characters

Character classes can be negated: [^[:CHAR-CLASS:]].

Equivalence classes

For example, the following not only matches an a, but also ä.

[[=a=]]

Links

http://www.adp-gmbh.ch/blog/2005/december/22.html