Re: [BUG] pg_dump does not properly deal with BEGIN ATOMIC function

Kirk Wolak <wolakk@gmail.com> writes:
> On Fri, Jun 2, 2023 at 8:16 AM Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> BTW, now that I see a case the default printout here seems
>> completely ridiculous.  I think we need to do
>> -       pg_log_info("  %s", buf);
>> +       pg_log_warning("  %s", buf);

>   If I comprehend the suggestion, it will label each line with a warning.
> Which implies I have 6 Warnings.

Right, I'd forgotten that pg_log_warning() will interpose "warning:".
Attached are two more-carefully-thought-out suggestions.  The easy
way is to use pg_log_warning_detail(), which produces output like

pg_dump: warning: could not resolve dependency loop among these items:
pg_dump: detail:   FUNCTION a_f  (ID 216 OID 40532)
pg_dump: detail:   CONSTRAINT a_pkey  (ID 3466 OID 40531)
pg_dump: detail:   POST-DATA BOUNDARY  (ID 3612)
pg_dump: detail:   TABLE DATA a  (ID 3610 OID 40525)
pg_dump: detail:   PRE-DATA BOUNDARY  (ID 3611)

Alternatively, we could assemble the details by hand, as in the
second patch, producing

pg_dump: warning: could not resolve dependency loop among these items:
  FUNCTION a_f  (ID 216 OID 40532)
  CONSTRAINT a_pkey  (ID 3466 OID 40531)
  POST-DATA BOUNDARY  (ID 3612)
  TABLE DATA a  (ID 3610 OID 40525)
  PRE-DATA BOUNDARY  (ID 3611)

I'm not really sure which of these I like better.  The first one
is a much simpler code change, and there is some value in labeling
the output like that.  The second patch's output seems less cluttered,
but it's committing a modularity sin by embedding formatting knowledge
at the caller level.  Thoughts?

BTW, there is a similar abuse of pg_log_info just a few lines
above this, and probably others elsewhere.  I won't bother
writing patches for other places till we have agreement on what
the output ought to look like.

            regards, tom lane

diff --git a/src/bin/pg_dump/pg_dump_sort.c b/src/bin/pg_dump/pg_dump_sort.c
index 745578d855..3c66b8bf1a 100644
--- a/src/bin/pg_dump/pg_dump_sort.c
+++ b/src/bin/pg_dump/pg_dump_sort.c
@@ -1253,7 +1253,7 @@ repairDependencyLoop(DumpableObject **loop,
         char        buf[1024];
 
         describeDumpableObject(loop[i], buf, sizeof(buf));
-        pg_log_info("  %s", buf);
+        pg_log_warning_detail("  %s", buf);
     }
 
     if (nLoop > 1)
diff --git a/src/bin/pg_dump/pg_dump_sort.c b/src/bin/pg_dump/pg_dump_sort.c
index 745578d855..f0eef849d3 100644
--- a/src/bin/pg_dump/pg_dump_sort.c
+++ b/src/bin/pg_dump/pg_dump_sort.c
@@ -971,6 +971,7 @@ static void
 repairDependencyLoop(DumpableObject **loop,
                      int nLoop)
 {
+    PQExpBuffer msgbuf;
     int            i,
                 j;
 
@@ -1247,14 +1248,17 @@ repairDependencyLoop(DumpableObject **loop,
      * If we can't find a principled way to break the loop, complain and break
      * it in an arbitrary fashion.
      */
-    pg_log_warning("could not resolve dependency loop among these items:");
+    msgbuf = createPQExpBuffer();
     for (i = 0; i < nLoop; i++)
     {
         char        buf[1024];
 
         describeDumpableObject(loop[i], buf, sizeof(buf));
-        pg_log_info("  %s", buf);
+        appendPQExpBuffer(msgbuf, "\n  %s", buf);
     }
+    pg_log_warning("could not resolve dependency loop among these items:%s",
+                   msgbuf->data);
+    destroyPQExpBuffer(msgbuf);
 
     if (nLoop > 1)
         removeObjectDependency(loop[0], loop[1]->dumpId);