Oracle® Database SQL Reference 10g Release 2 (10.2) Part Number B14200-01 |
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Syntax
Purpose
COMPOSE
takes as its argument a string, or an expression that resolves to a string, in any datatype, and returns a Unicode string in its fully normalized form in the same character set as the input. char
can be any of the datatypes CHAR
, VARCHAR2
, NCHAR
, NVARCHAR2
, CLOB
, or NCLOB
. For example, an o
code point qualified by an umlaut code point will be returned as the o-umlaut code point.
CLOB
and NCLOB
values are supported through implicit conversion. If char
is a character LOB value, it is converted to a VARCHAR
value before the COMPOSE
operation. The operation will fail if the size of the LOB value exceeds the supported length of the VARCHAR
in the particular development environment.
See Also: Oracle Database Globalization Support Guide for information on Unicode character sets and character semantics |
Examples
The following example returns the o-umlaut code point:
SELECT COMPOSE ( 'o' || UNISTR('\0308') ) FROM DUAL; CO -- ö