Doc: explain how to test ADMIN privilege with pg_has_role().

This has always been possible, but the syntax is a bit obscure,
and our user-facing docs were not very helpful.  Spell it out
more clearly.

Per complaint from Dominique Devienne.  Back-patch to
all supported branches.

Discussion: https://postgr.es/m/CAFCRh-8JNEy+dV4SXFOrWca50u+d=--TO4cq=+ac1oBtfJy4AA@mail.gmail.com

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 6f75bd0c7d25638490421930bac17cfe6c385679..e39d524b6bd1e65b20fdb153f0a38032ed46f63a 100644 (file)
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -25289,6 +25289,10 @@ SELECT has_function_privilege('joeuser', 'myfunc(int, text)', 'execute');
         are immediately available without doing SET ROLE,
         while SET denotes whether it is possible to change
         to the role using the SET ROLE command.
+        WITH ADMIN OPTION or WITH GRANT
+        OPTION can be added to any of these privilege types to
+        test whether the ADMIN privilege is held (all
+        six spellings test the same thing).
         This function does not allow the special case of
         setting user to public,
         because the PUBLIC pseudo-role can never be a member of real roles.