perintah sql dasar menggunakan union

yuli@yulychocho:~$ mysql -u root -p
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mysql> select nama from artis UNION select nama_artis from info_artis;
ERROR 1046 (3D000): No database selected
mysql> use yuliyanti;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed
mysql> select nama from artis UNION select nama_artis from info_artis;
+--------------------+
| nama               |
+--------------------+
| DREW BARRYMORE     |
| SHARON STONE       |
| SYLVESTER STALLONE |
| KEVIN COSTER       |
| JULLA ROBERT       |
| DEMI MO0RE         |
| CINDY CRAWFORD     |
| CAMERON DLAZ       |
| KEANU REEVES       |
| SANDRA BULLOK      |
| RICHARD GERE       |
| DEMI MOORE         |
| ANGELINA JOLIE     |
| SANDRA BULLOCK     |
| SYLVESTER STALLON  |
+--------------------+
15 rows in set (0,03 sec)

mysql> create table air(
    -> air varchar(20));
Query OK, 0 rows affected (0,68 sec)

mysql> insert into air values ("katak");
Query OK, 1 row affected (0,06 sec)

mysql> insert into air values ("ikan mas");
Query OK, 1 row affected (0,35 sec)

mysql> insert into air values ("ular");
Query OK, 1 row affected (0,06 sec)

mysql> insert into air values ("ikan hiu");
Query OK, 1 row affected (0,12 sec)

mysql> create table darat(darat varchar(20));
Query OK, 0 rows affected (2,04 sec)

mysql> insert into darat values ("katak");
Query OK, 1 row affected (0,07 sec)

mysql> insert into darat values ("kuda");
Query OK, 1 row affected (0,12 sec)

mysql> insert into darat values ("ular");
Query OK, 1 row affected (0,29 sec)

mysql> insert into darat values ("kucing");
Query OK, 1 row affected (0,06 sec)

mysql> select air from air UNION select darat from darat;
+----------+
| air      |
+----------+
| katak    |
| ikan mas |
| ular     |
| ikan hiu |
| kuda     |
| kucing   |
+----------+
6 rows in set (0,00 sec)

mysql> select * from pegawai where gaji = (select max(gaji) from pegawai);
+-----+------------+--------+------------+--------+
| nip | nama       | gaji   | departemen | kota   |
+-----+------------+--------+------------+--------+
| 4   | kadarisman | 960000 | akunting   | sleman |
+-----+------------+--------+------------+--------+
1 row in set (0,05 sec)