Add test coverage for "unchanged toast column" replication code path.

tglsfdc · tglsfdc · commit 8b46acf7c423 · 2019-11-22T12:52:26.000-05:00
It seems pretty unacceptable to have no regression test coverage for this aspect of the logical replication protocol, especially given the bugs we've found in related code. Discussion: https://postgr.es/m/16129-a0c0f48e71741e5f@postgresql.org
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 19;
+use Test::More tests => 21;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -157,9 +157,40 @@
 local|2.2|bar|2),
 	'update works with different column order and subscriber local values');
 
+# check behavior with toasted values
+
+$node_publisher->safe_psql('postgres',
+	"UPDATE tab_mixed SET b = repeat('xyzzy', 100000) WHERE a = 2");
+
+$node_publisher->poll_query_until('postgres', $caughtup_query)
+  or die "Timed out while waiting for subscriber to catch up";
+
+$result = $node_subscriber->safe_psql('postgres',
+	"SELECT a, length(b), c, d FROM tab_mixed ORDER BY a");
+is( $result, qq(1|3|1.1|local
+2|500000|2.2|local),
+	'update transmits large column value');
+
+$node_publisher->safe_psql('postgres',
+	"UPDATE tab_mixed SET c = 3.3 WHERE a = 2");
+
+$node_publisher->poll_query_until('postgres', $caughtup_query)
+  or die "Timed out while waiting for subscriber to catch up";
+
+$result = $node_subscriber->safe_psql('postgres',
+	"SELECT a, length(b), c, d FROM tab_mixed ORDER BY a");
+is( $result, qq(1|3|1.1|local
+2|500000|3.3|local),
+	'update with non-transmitted large column value');
+
 # check behavior with dropped columns
 
+# this update should get transmitted before the column goes away
+$node_publisher->safe_psql('postgres',
+	"UPDATE tab_mixed SET b = 'bar', c = 2.2 WHERE a = 2");
+
 $node_publisher->safe_psql('postgres', "ALTER TABLE tab_mixed DROP COLUMN b");
+
 $node_publisher->safe_psql('postgres',
 	"UPDATE tab_mixed SET c = 11.11 WHERE a = 1");
 
