Improve release note text about set-returning-function changes.

Paul Ramsey griped about this awhile ago, but I'd been holding fire
on changing it until we settled what to do about the CASE/COALESCE
issue.

Discussion: https://postgr.es/m/CACowWR0AMyUt5fwtvuDqWyYNdp-hQJj9XqSxJR6YM9sKWov=_w@mail.gmail.com

diff --git a/doc/src/sgml/release-10.sgml b/doc/src/sgml/release-10.sgml
index b10086bdb0f0459a35ea966e182d115d4275715d..75c48c0f59070996982dff98065543afcaf1361f 100644 (file)
--- a/doc/src/sgml/release-10.sgml
+++ b/doc/src/sgml/release-10.sgml
@@ -129,18 +129,29 @@
 
     
 
      
-      Allow COALESCE and CASE to return multiple
-      rows when evaluating set-returning functions (Andres Freund).
+      Change the implementation of set-returning functions appearing in
+      a query's SELECT list (Andres Freund)
      
 
      
-      This also prevents conditionals like CASE from
-      controlling the execution of set-returning functions because
-      set-returning functions are now executed earlier.
+      Set-returning functions are now evaluated before evaluation of scalar
+      expressions in the SELECT list, much as though they had
+      been placed in a LATERAL FROM-clause item.  This allows
+      saner semantics for cases where multiple set-returning functions are
+      present.  If they return different numbers of rows, the shorter results
+      are extended to match the longest result by adding nulls.  Previously
+      the results were cycled until they all terminated at the same time,
+      producing a number of rows equal to the least common multiple of the
+      functions' periods.  In addition, set-returning functions are now
+      disallowed within CASE and COALESCE constructs.
+      For more information
+      see .
      
     
 
@@ -1701,20 +1712,6 @@
       
      
 
-     
-
-      
-       Fix check_srf_call_placement() to handle
-       VALUES cases correctly (Tom Lane)
-      
-
-      
-      NEED TEXT.
-      
-     
-