Pipeline mode disallows multicommand strings

... so mention that in appropriate places of the libpq docs.

Backpatch to 14.

Reported-by: RekGRpth 
Discussion: https://postgr.es/m/17235-53bb38fc5be593dc@postgresql.org

diff --git a/doc/src/sgml/libpq.sgml b/doc/src/sgml/libpq.sgml
index b449c834a95b8a6be41a30653bdb28067b5c9d0c..c17d33a54f09d60ed8a4b3935c0d15ff3e31ca94 100644 (file)
--- a/doc/src/sgml/libpq.sgml
+++ b/doc/src/sgml/libpq.sgml
@@ -4594,6 +4594,11 @@ int PQsendQuery(PGconn *conn, const char *command);
        (on the same connection) until 
        has returned a null pointer, indicating that the command is done.
       
+
+      
+       In pipeline mode, command strings containing more than one SQL command
+       are disallowed.
+      
      
     
 
@@ -5046,7 +5051,8 @@ int PQflush(PGconn *conn);
      can be used
     to test whether pipeline mode is active.
     In pipeline mode, only asynchronous operations
-    are permitted, and COPY is disallowed.
+    are permitted, command strings containing multiple SQL commands are
+    disallowed, and so is COPY.
     Using synchronous command execution functions
     such as PQfn,
     PQexec,