pg_dump: Add --sequence-data.

This new option instructs pg_dump to dump sequence data when the
--no-data, --schema-only, or --statistics-only option is specified.
This was originally considered for commit a7e5457, but it was
left out at that time because there was no known use-case.  A
follow-up commit will use this to optimize pg_upgrade's file
transfer step.

Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Discussion: https://postgr.es/m/Zyvop-LxLXBLrZil%40nathan

Author: nathan-bossart

doc/src/sgml/ref/pg_dump.sgml

@@ -1298,6 +1298,17 @@ PostgreSQL documentation
        </listitem>
      </varlistentry>
 
+     <varlistentry>
+      <term><option>--sequence-data</option></term>
+      <listitem>
+       <para>
+        Include sequence data in the dump.  This is the default behavior except
+        when <option>--no-data</option>, <option>--schema-only</option>, or
+        <option>--statistics-only</option> is specified.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry>
       <term><option>--serializable-deferrable</option></term>
       <listitem>

src/bin/pg_dump/pg_dump.c

@@ -518,6 +518,7 @@ main(int argc, char **argv)
 		{"sync-method", required_argument, NULL, 15},
 		{"filter", required_argument, NULL, 16},
 		{"exclude-extension", required_argument, NULL, 17},
+		{"sequence-data", no_argument, &dopt.sequence_data, 1},
 
 		{NULL, 0, NULL, 0}
 	};
@@ -801,14 +802,6 @@ main(int argc, char **argv)
 	if (dopt.column_inserts && dopt.dump_inserts == 0)
 		dopt.dump_inserts = DUMP_DEFAULT_ROWS_PER_INSERT;
 
-	/*
-	 * Binary upgrade mode implies dumping sequence data even in schema-only
-	 * mode.  This is not exposed as a separate option, but kept separate
-	 * internally for clarity.
-	 */
-	if (dopt.binary_upgrade)
-		dopt.sequence_data = 1;
-
 	if (data_only && schema_only)
 		pg_fatal("options -s/--schema-only and -a/--data-only cannot be used together");
 	if (schema_only && statistics_only)
@@ -1275,6 +1268,7 @@ help(const char *progname)
 	printf(_("  --quote-all-identifiers      quote all identifiers, even if not key words\n"));
 	printf(_("  --rows-per-insert=NROWS      number of rows per INSERT; implies --inserts\n"));
 	printf(_("  --section=SECTION            dump named section (pre-data, data, or post-data)\n"));
+	printf(_("  --sequence-data              include sequence data in dump\n"));
 	printf(_("  --serializable-deferrable    wait until the dump can run without anomalies\n"));
 	printf(_("  --snapshot=SNAPSHOT          use given snapshot for the dump\n"));
 	printf(_("  --statistics-only            dump only the statistics, not schema or data\n"));

src/bin/pg_dump/t/002_pg_dump.pl

@@ -66,6 +66,7 @@
 			'--file' => "$tempdir/binary_upgrade.dump",
 			'--no-password',
 			'--no-data',
+			'--sequence-data',
 			'--binary-upgrade',
 			'--dbname' => 'postgres',    # alternative way to specify database
 		],

src/bin/pg_upgrade/dump.c

@@ -52,7 +52,7 @@ generate_old_dump(void)
 		snprintf(log_file_name, sizeof(log_file_name), DB_DUMP_LOG_FILE_MASK, old_db->db_oid);
 
 		parallel_exec_prog(log_file_name, NULL,
-						   "\"%s/pg_dump\" %s --no-data %s --quote-all-identifiers "
+						   "\"%s/pg_dump\" %s --no-data %s --sequence-data --quote-all-identifiers "
 						   "--binary-upgrade --format=custom %s --no-sync --file=\"%s/%s\" %s",
 						   new_cluster.bindir, cluster_conn_opts(&old_cluster),
 						   log_opts.verbose ? "--verbose" : "",

src/test/modules/test_pg_dump/t/001_base.pl

@@ -48,7 +48,7 @@
 		dump_cmd => [
 			'pg_dump', '--no-sync',
 			'--file' => "$tempdir/binary_upgrade.sql",
-			'--schema-only', '--binary-upgrade',
+			'--schema-only', '--sequence-data', '--binary-upgrade',
 			'--dbname' => 'postgres',
 		],
 	},