pg_dump: Fix array literals in fetchAttributeStats().

Presently, fetchAttributeStats() builds array literals by treating
the elements as SQL identifiers.  This is incorrect for a couple of
reasons:

* Array literal content must match the external text representation
  of the array, i.e., what array_out() would return.  One notable
  problem is that double quotes are escaped with "" in identifiers
  but with \" in array literals.  To fix, build the array content
  using the pre-existing appendPGArray() function.

* Array literals must be written as string constants.  A notable
  problem here is that single quotes are escaped via '' in strings
  but are not escaped in the text representation of an array.  To
  fix, append the aforementioned array literal content to the query
  with appendStringLiteralAH().

While at it, modify a test case to use an identifier that would
cause the test to fail without this change.

Oversight in commit 9c02e3a986.

Reported-by: Philippe Beaudoin <[email protected]>
Author: Jian He <[email protected]>
Co-authored-by: Nathan Bossart <[email protected]>
Co-authored-by: Stepan Neretin <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Bug: #18923
Discussion: https://postgr.es/m/18923-e79273f87c6bed69%40postgresql.org

2 files changed, 16 insertions, 11 deletions

diff --git a/src/bin/pg_dump/pg_dump.c b/src/bin/pg_dump/pg_dump.c
index e2e7975b34e..c73e73a87d1 100644
--- a/src/bin/pg_dump/pg_dump.c
+++ b/src/bin/pg_dump/pg_dump.c
@@ -10765,6 +10765,9 @@ fetchAttributeStats(Archive *fout)
 		restarted = true;
 	}
 
+	appendPQExpBufferChar(nspnames, '{');
+	appendPQExpBufferChar(relnames, '{');
+
 	/*
 	 * Scan the TOC for the next set of relevant stats entries.  We assume
 	 * that statistics are dumped in the order they are listed in the TOC.
@@ -10776,23 +10779,25 @@ fetchAttributeStats(Archive *fout)
 		if ((te->reqs & REQ_STATS) != 0 &&
 			strcmp(te->desc, "STATISTICS DATA") == 0)
 		{
-			appendPQExpBuffer(nspnames, "%s%s", count ? "," : "",
-							  fmtId(te->namespace));
-			appendPQExpBuffer(relnames, "%s%s", count ? "," : "",
-							  fmtId(te->tag));
+			appendPGArray(nspnames, te->namespace);
+			appendPGArray(relnames, te->tag);
 			count++;
 		}
 	}
 
+	appendPQExpBufferChar(nspnames, '}');
+	appendPQExpBufferChar(relnames, '}');
+
 	/* Execute the query for the next batch of relations. */
 	if (count > 0)
 	{
 		PQExpBuffer query = createPQExpBuffer();
 
-		appendPQExpBuffer(query, "EXECUTE getAttributeStats("
-						  "'{%s}'::pg_catalog.name[],"
-						  "'{%s}'::pg_catalog.name[])",
-						  nspnames->data, relnames->data);
+		appendPQExpBufferStr(query, "EXECUTE getAttributeStats(");
+		appendStringLiteralAH(query, nspnames->data, fout);
+		appendPQExpBufferStr(query, "::pg_catalog.name[],");
+		appendStringLiteralAH(query, relnames->data, fout);
+		appendPQExpBufferStr(query, "::pg_catalog.name[])");
 		res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
 		destroyPQExpBuffer(query);
 	}
diff --git a/src/bin/pg_dump/t/002_pg_dump.pl b/src/bin/pg_dump/t/002_pg_dump.pl
index 55d892d9c16..cf34f71ea11 100644
--- a/src/bin/pg_dump/t/002_pg_dump.pl
+++ b/src/bin/pg_dump/t/002_pg_dump.pl
@@ -4834,13 +4834,13 @@ my %tests = (
 			CREATE TABLE dump_test.has_stats
 			AS SELECT g.g AS x, g.g / 2 AS y FROM generate_series(1,100) AS g(g);
 			CREATE MATERIALIZED VIEW dump_test.has_stats_mv AS SELECT * FROM dump_test.has_stats;
-			CREATE INDEX dup_test_post_data_ix ON dump_test.has_stats(x, (x - 1));
+			CREATE INDEX """dump_test""\'s post-data index" ON dump_test.has_stats(x, (x - 1));
 			ANALYZE dump_test.has_stats, dump_test.has_stats_mv;',
 		regexp => qr/^
 			\QSELECT * FROM pg_catalog.pg_restore_relation_stats(\E\s+
 			'version',\s'\d+'::integer,\s+
 			'schemaname',\s'dump_test',\s+
-			'relname',\s'dup_test_post_data_ix',\s+
+			'relname',\s'"dump_test"''s\ post-data\ index',\s+
 			'relpages',\s'\d+'::integer,\s+
 			'reltuples',\s'\d+'::real,\s+
 			'relallvisible',\s'\d+'::integer,\s+
@@ -4849,7 +4849,7 @@ my %tests = (
 			\QSELECT * FROM pg_catalog.pg_restore_attribute_stats(\E\s+
 			'version',\s'\d+'::integer,\s+
 			'schemaname',\s'dump_test',\s+
-			'relname',\s'dup_test_post_data_ix',\s+
+			'relname',\s'"dump_test"''s\ post-data\ index',\s+
 			'attnum',\s'2'::smallint,\s+
 			'inherited',\s'f'::boolean,\s+
 			'null_frac',\s'0'::real,\s+