Clarify that surrogate pairs are not encoded in UTF-8 directly

diff --git a/doc/src/sgml/syntax.sgml b/doc/src/sgml/syntax.sgml
index ca092b5ae6e50bfc21ff4e69e30d5e6f5d4da1a3..18582b9216c772a7c002d73f84f9087573285ce6 100644 (file)
--- a/doc/src/sgml/syntax.sgml
+++ b/doc/src/sgml/syntax.sgml
@@ -1,4 +1,4 @@
-
+
 
 
  SQL Syntax
@@ -236,12 +236,15 @@ U&"d!0061t!+000061" UESCAPE '!'
 
    
     The Unicode escape syntax works only when the server encoding is
-    UTF8.  When other server encodings are used, only code points in
-    the ASCII range (up to \007F) can be specified.
-    Both the 4-digit and the 6-digit form can be used to specify
-    UTF-16 surrogate pairs to compose characters with code points
-    larger than U+FFFF (although the availability of
-    the 6-digit form technically makes this unnecessary).
+    UTF8.  When other server encodings are used, only code
+    points in the ASCII range (up to \007F) can be
+    specified.  Both the 4-digit and the 6-digit form can be used to
+    specify UTF-16 surrogate pairs to compose characters with code
+    points larger than U+FFFF, although the availability of the
+    6-digit form technically makes this unnecessary.  (When surrogate
+    pairs are used when the server encoding is UTF8, they
+    are first combined into a single code point that is then encoded
+    in UTF-8.)
    
 
    
@@ -431,13 +434,15 @@ SELECT 'foo'      'bar';
 
     
      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 \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 U+FFFF (although the
-     availability of the 8-digit form technically makes this
-     unnecessary).
+     encoding is UTF8.  When other server encodings are
+     used, only code points in the ASCII range (up
+     to \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 U+FFFF, although
+     the availability of the 8-digit form technically makes this
+     unnecessary.  (When surrogate pairs are used when the server
+     encoding is UTF8, they are first combined into a
+     single code point that is then encoded in UTF-8.)
     
 
     
@@ -517,13 +522,15 @@ U&'d!0061t!+000061' UESCAPE '!'
 
     
      The Unicode escape syntax works only when the server encoding is
-     UTF8.  When other server encodings are used, only code points in
-     the ASCII range (up to \007F) can be
-     specified.
-     Both the 4-digit and the 6-digit form can be used to specify
-     UTF-16 surrogate pairs to compose characters with code points
-     larger than U+FFFF (although the availability
-     of the 6-digit form technically makes this unnecessary).
+     UTF8.  When other server encodings are used, only
+     code points in the ASCII range (up to \007F)
+     can be specified.  Both the 4-digit and the 6-digit form can be
+     used to specify UTF-16 surrogate pairs to compose characters with
+     code points larger than U+FFFF, although the availability of the
+     6-digit form technically makes this unnecessary.  (When surrogate
+     pairs are used when the server encoding is UTF8, they
+     are first combined into a single code point that is then encoded
+     in UTF-8.)