diff options
Diffstat (limited to 'doc/src')
| -rw-r--r-- | doc/src/sgml/syntax.sgml | 34 |
1 files changed, 27 insertions, 7 deletions
diff --git a/doc/src/sgml/syntax.sgml b/doc/src/sgml/syntax.sgml index c805e2e7141..73db3235bd6 100644 --- a/doc/src/sgml/syntax.sgml +++ b/doc/src/sgml/syntax.sgml @@ -1,4 +1,4 @@ -<!-- $PostgreSQL: pgsql/doc/src/sgml/syntax.sgml,v 1.135 2009/09/21 22:22:07 petere Exp $ --> +<!-- $PostgreSQL: pgsql/doc/src/sgml/syntax.sgml,v 1.136 2009/09/22 23:52:53 petere Exp $ --> <chapter id="sql-syntax"> <title>SQL Syntax</title> @@ -398,6 +398,14 @@ SELECT 'foo' 'bar'; </entry> <entry>hexadecimal byte value</entry> </row> + <row> + <entry> + <literal>\u<replaceable>xxxx</replaceable></literal>, + <literal>\U<replaceable>xxxxxxxx</replaceable></literal> + (<replaceable>x</replaceable> = 0 - 9, A - F) + </entry> + <entry>16 or 32-bit hexadecimal Unicode character value</entry> + </row> </tbody> </tgroup> </table> @@ -411,13 +419,25 @@ SELECT 'foo' 'bar'; </para> <para> - It is your responsibility that the byte sequences you create are + It is your responsibility that the byte sequences you create, + especially when using the octal or hexadecimal escapes, compose valid characters in the server character set encoding. When the - server encoding is UTF-8, then the alternative Unicode escape - syntax, explained in <xref linkend="sql-syntax-strings-uescape">, - should be used instead. (The alternative would be doing the - UTF-8 encoding by hand and writing out the bytes, which would be - very cumbersome.) + server encoding is UTF-8, then the Unicode escapes or the + alternative Unicode escape syntax, explained + in <xref linkend="sql-syntax-strings-uescape">, should be used + instead. (The alternative would be doing the UTF-8 encoding by + hand and writing out the bytes, which would be very cumbersome.) + </para> + + <para> + The Unicode escape syntax works fully only when the server + encoding is UTF-8. When other server encodings are used, only + code points in the ASCII range (up to <literal>\u007F</>) can be + specified. Both the 4-digit and the 8-digit form can be used to + specify UTF-16 surrogate pairs to compose characters with code + points larger than <literal>\FFFF</literal> (although the + availability of the 8-digit form technically makes this + unnecessary). </para> <caution> |