Point to LISTAGG documentation for LIST

Author: mrotteveel

doc/sql.extensions/README.list

@@ -1,40 +1,5 @@
 SQL Language Extension: LIST
 
-Function:
-    This function returns a string result with the concatenated non-NULL
-    values from a group. It returns NULL if there are no non-NULL values.
+Since Firebird 6.0, LIST is an alias for the SQL standard function LISTAGG.
 
-Authors:
-    Oleg Loa <loa@mail.ru>
-    Dmitry Yemanov <dimitr@firebird.org>
-
-Format:
-
-  <list function> ::=
-      LIST '(' [ {ALL | DISTINCT} ] <value expression> [',' <delimiter value> ] ')'
-
-  <delimiter value> ::=
-      { <string literal> | <parameter> | <variable> }
-
-Syntax Rules:
-    1) If neither ALL nor DISTINCT is specified, ALL is implied.
-    2) If <delimiter value> is omitted, a comma is used to separate
-       the concatenated values.
-
-Notes:
-    1) Numeric and datetime values are implicitly converted to strings
-       during evaluation.
-    2) The result value is of type BLOB with SUB_TYPE TEXT for all cases
-       except list of BLOB with different subtype.
-    3) Ordering of values within a group is implementation-defined.
-
-Examples:
-
-A)
-  SELECT LIST(ID, ':')
-  FROM MY_TABLE
-
-B)
-  SELECT TAG_TYPE, LIST(TAG_VALUE)
-  FROM TAGS
-  GROUP BY TAG_TYPE
+See README.listagg for more information.