Docs.

doc/WhatsNew

@@ -408,6 +408,8 @@
 
     * Feature CORE-964
         Aggregate function LIST (string concatenation)
+      See also:
+        /doc/sql.extensions/README.list
       Contributor(s):
         Dmitry Yemanov <dimitr at firebirdsql.org>
 

doc/sql.extensions/README.list

@@ -0,0 +1,41 @@
+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.
+
+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 VARCHAR(32765), so the LIST function
+       should be used carefully, as Firebird limits the maximum
+       result set width by 64KB.
+    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