diff --git a/doc/sql.extensions/README.hex_literals.txt b/doc/sql.extensions/README.hex_literals.txt
index d2942bc4d4..add4a1b3ac 100644
--- a/doc/sql.extensions/README.hex_literals.txt
+++ b/doc/sql.extensions/README.hex_literals.txt
@@ -14,7 +14,8 @@ Syntax:
     { 0x | 0X } <hexit> [ <hexit>... ]
 
 <binary string literal> ::=
-    { x | X } <quote> [ { <hexit> <hexit> }... ] <quote>
+    { x | X } <quote> [ <space>... ] [ { <hexit> [ <space>... ] <hexit> [ <space>... ] }... ] <quote>
+        [ { <separator> <quote> [ <space>... ] [ { <hexit> [ <space>... ] <hexit> [ <space>... ] }... ] <quote> }... ]
 
 <digit> ::=
     0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9