Oracle10g Regular Expression

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• Equivalence classes

Regular Expressions in oraclewith 10g, regular expressions are finally available in SQL. That is, they were already supported through the specified package. The new operators and functions are regexp_like

symbol	matches
.	Any character t 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 classesthe 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 classesfor example, the following not only matches A , But also Ä .

 
[[= A =]
 

Links

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