Add psql tab compression for SET COMPRESSION with ALTER TABLE

Author: Aleksander Alekseev
Reviewed-by: Shinya Kato
Discussion: https://postgr.es/m/CAJ7c6TMuT+=P7uDepjVpdqSEp2xOmXET3Y2K-xWAO=sCz-28gg@mail.gmail.com

Author: michaelpq

src/bin/psql/tab-complete.c

@@ -2385,6 +2385,10 @@ psql_completion(const char *text, int start, int end)
 	else if (Matches("ALTER", "TABLE", MatchAny, "ALTER", "COLUMN", MatchAny, "SET", "(") ||
 			 Matches("ALTER", "TABLE", MatchAny, "ALTER", MatchAny, "SET", "("))
 		COMPLETE_WITH("n_distinct", "n_distinct_inherited");
+	/* ALTER TABLE ALTER [COLUMN] <foo> SET COMPRESSION */
+	else if (Matches("ALTER", "TABLE", MatchAny, "ALTER", "COLUMN", MatchAny, "SET", "COMPRESSION") ||
+			 Matches("ALTER", "TABLE", MatchAny, "ALTER", MatchAny, "SET", "COMPRESSION"))
+		COMPLETE_WITH("DEFAULT", "PGLZ", "LZ4");
 	/* ALTER TABLE ALTER [COLUMN] <foo> SET STORAGE */
 	else if (Matches("ALTER", "TABLE", MatchAny, "ALTER", "COLUMN", MatchAny, "SET", "STORAGE") ||
 			 Matches("ALTER", "TABLE", MatchAny, "ALTER", MatchAny, "SET", "STORAGE"))