Add pg_all_utf8() which returns all valid UTF-8 characters.

README.md

@@ -242,6 +242,17 @@ than 1114111.
 ### text pg_utf8(code integer)
 Alias of [pg_chr](https://github.com/MasaoFujii/pg_cheat_funcs#text-pg_chrcode-integer) function.
 
+### SETOF record pg_all_utf8()
+Return all valid UTF-8 characters.
+This function returns a record, shown in the table below.
+
+| Column Name | Data Type | Description       |
+|-------------|-----------|-------------------|
+| code        | text      | code of character |
+| utf8        | text      | UTF-8 character   |
+
+This function can be executed only under UTF-8 database encoding.
+
 ### text pg_eucjp(code1 bit(8), code2 bit(8), code3 bit(8))
 Return EUC_JP character with the given codes.
 The following table shows the valid combination of the codes.

pg_cheat_funcs--1.0.sql

@@ -176,6 +176,13 @@ RETURNS text
 AS 'MODULE_PATHNAME', 'pg_chr'
 LANGUAGE C STRICT IMMUTABLE;
 
+CREATE FUNCTION pg_all_utf8(OUT code integer, OUT utf8 text)
+RETURNS SETOF record AS
+'SELECT * FROM
+    (SELECT code, pg_utf8(code) utf8 FROM generate_series(0, 1114111) code) tmp
+ WHERE utf8 IS NOT NULL'
+LANGUAGE SQL IMMUTABLE;
+
 CREATE FUNCTION pg_eucjp(bit(8), bit(8) DEFAULT 'x00', bit(8) DEFAULT 'x00')
 RETURNS text
 AS 'MODULE_PATHNAME'