Oracle Regular Expressions Pocket Reference

Name

[: :] (Character Class) — Specifies a character class

Synopsis

Use [: and :] to enclose a character class name, for example: [:alpha:]. Character classes must be specified within bracket expressions, as in [[:alpha:]].

The following example uses the character class [:digit:] to match the digits in a ZIP code:

SELECT REGEXP_SUBSTR(
   'Munising MI 49862',
   '[[:digit:]]{5}') zip_code
FROM dual;

49862

In this example, we could just as well have used the pattern [0-9]{5}. However, in multilingual environments digits are not always the characters 0-9. The character class [:digit:] matches the English 0-9, the Arabic-Indic ٠–٩, the Tibetan ༠–༩, and so forth.

Table 1-5 describes the character class names recognized by Oracle. All names are case-sensitive.

Table 1-5. Supported character classes

Class	Description
[:alnum:]	Alphanumeric characters (same as [:alpha:] + [:digit:])
[:alpha:]	Alphabetic characters only
[:blank:]	Blank space characters, such as space and tab
[:cntrl:]	Nonprinting or control characters
[:digit:]	Numeric digits
[:graph:]	Graphical characters (same as [:punct:] + [:upper:] + [:lower:] + [:digit:])
[:lower:]	Lowercase letters
[:print:]	Printable characters
[:punct:]	Punctuation characters
[:space:]	Whitespace characters such as space, form-feed, newline,carriage return, horizontal tab, and vertical tab
[:upper:]	Uppercase letters
[:xdigit:]	Hexadecimal characters