Document BETWEEN.

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index cf4ac7f7ac7055965c9c0abde3b614956c2edc6b..5e10ded524252662ad3d920663934557a560121c 100644 (file)
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -1,4 +1,4 @@
-
+
 
 
  Functions and Operators
@@ -185,6 +185,29 @@
    3).
   
 
+  
+   In addition to the comparison operators, the special
+   BETWEEN construct is available.
+
+a BETWEEN x AND y
+
+   is equivalent to
+
+a >= x AND a <= y
+
+   Similarly,
+
+a NOT BETWEEN x AND y
+
+   is equivalent to
+
+a < x OR a > y
+
+   There is no difference between the two respective forms apart from
+   the CPU cycles required to rewrite the first one
+   into the second one internally.
+  
+
   
    To check whether a value is or is not NULL, use the constructs