Oracle10g Multilingual Regular Expression Syntax
The next table lists the full set of operators defined in the
POSIX standard Extended Regular Expression (ERE) syntax. Oracle
follows the exact syntax and matching semantics for these
operators, as defined in the POSIX standard for matching ASCII
(English language) data. The notes following the table provide
more complete descriptions of the operators and their functions,
as well as Oracle multilingual enhancements of the operators. The
table following the notes summarizes Oracle support for and
Multilingual enhancement of the POSIX operators.
|
OPERATOR |
DESCRIPTION |
|
\ (1) |
The backslash character can
have four different meanings, depending on the context. It
can: Stand for itself, Quote the next character, Introduce an
operator, Do nothing |
|
* |
Matches zero or more
occurrences |
|
+ |
Matches one or more
occurrences |
|
? |
Matches zero or one occurrence |
|
| |
Alternation operator for
specifying alternative matches |
|
^ (2) |
Matches the beginning-of-line
character |
|
$ (2) |
Matches the end-of-line
character |
|
. (3) |
Matches any character in the
supported character set except NULL |
|
[ ] (4) |
Bracket expression for
specifying a matching list that should match any one of the
expressions represented in the list. A non-matching list
expression begins with a circumflex (^) and specifies a list
that matches any character except for the expressions
represented in the list. |
|
( ) |
Grouping expression, treated
as a single subexpression |
|
{m} |
Matches exactly m times |
|
{m,} |
Matches at least m times |
|
{m,n} |
Matches at least m times but
no more than n times |
Table 6.5 Regular Expression Operators and Metasymbols |
