~/mysql >mysql --user=cs4010 --password=cs4010 --database=cs4010 Reading table information for completion of table and column names You can turn off this feature to get a quicker startup with -A Welcome to the MariaDB monitor. Commands end with ; or \g. Your MariaDB connection id is 124 Server version: 5.5.41-MariaDB MariaDB Server Copyright (c) 2000, 2014, Oracle, MariaDB Corporation Ab and others. Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. MariaDB [cs4010]> SET @name_test='Joe Jones'; Query OK, 0 rows affected (0.00 sec) MariaDB [cs4010]> SELECT * FROM student WHERE name=@name_test; +------------+-----------+--------+------+ | student_id | name | year | test | +------------+-----------+--------+------+ | 1 | Joe Jones | Senior | 85 | +------------+-----------+--------+------+ 1 row in set (0.00 sec) MariaDB [cs4010]> source test3.sql Query OK, 0 rows affected (0.00 sec) +------------+-----------+--------+------+ | student_id | name | year | test | +------------+-----------+--------+------+ | 3 | Sam Smith | Junior | 90 | +------------+-----------+--------+------+ 1 row in set (0.00 sec) +------+ | test | +------+ | 90 | MariaDB [cs4010]> create table student_athlete as select * from student a,athlete b where b.this_student=a.student_id; Query OK, 1 row affected (0.00 sec) Records: 1 Duplicates: 0 Warnings: 0 MariaDB [cs4010]> select * from student_athlete; +------------+-----------+--------+------+--------------+----------+ | student_id | name | year | test | this_student | sport | +------------+-----------+--------+------+--------------+----------+ | 3 | Sam Smith | Junior | 90 | 3 | Baseball | +------------+-----------+--------+------+--------------+----------+ 1 row in set (0.00 sec) MariaDB [cs4010]> alter table student_athlete drop this_student; Query OK, 1 row affected (0.00 sec) Records: 1 Duplicates: 0 Warnings: 0 MariaDB [cs4010]> describe student_athlete; +------------+--------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +------------+--------------+------+-----+---------+-------+ | student_id | int(11) | NO | | 0 | | | name | varchar(255) | NO | | NULL | | | year | varchar(20) | YES | | NULL | | | test | int(11) | YES | | NULL | | | sport | varchar(255) | NO | | NULL | | +------------+--------------+------+-----+---------+-------+ 5 rows in set (0.00 sec) MariaDB [cs4010]> insert into student_athlete (student_id,name) values (3,"Joe Jones"); Query OK, 1 row affected, 1 warning (0.00 sec) MariaDB [cs4010]> select * from student_athlete; +------------+-----------+--------+------+----------+ | student_id | name | year | test | sport | +------------+-----------+--------+------+----------+ | 3 | Sam Smith | Junior | 90 | Baseball | | 3 | Joe Jones | NULL | NULL | | +------------+-----------+--------+------+----------+ 2 rows in set (0.00 sec) MariaDB [cs4010]> delete from student_athlete where name="Joe Jones"; Query OK, 1 row affected (0.00 sec) MariaDB [cs4010]> select * from student_athlete; +------------+-----------+--------+------+----------+ | student_id | name | year | test | sport | +------------+-----------+--------+------+----------+ | 3 | Sam Smith | Junior | 90 | Baseball | +------------+-----------+--------+------+----------+ 1 row in set (0.00 sec) MariaDB [cs4010]> alter table student_athlete add primary key (student_id); Query OK, 0 rows affected (0.01 sec) Records: 0 Duplicates: 0 Warnings: 0 MariaDB [cs4010]> describe student_athlete; +------------+--------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +------------+--------------+------+-----+---------+-------+ | student_id | int(11) | NO | PRI | 0 | | | name | varchar(255) | NO | | NULL | | | year | varchar(20) | YES | | NULL | | | test | int(11) | YES | | NULL | | | sport | varchar(255) | NO | | NULL | | +------------+--------------+------+-----+---------+-------+ 5 rows in set (0.00 sec) MariaDB [cs4010]> insert into student_athlete (student_id,name) values (3,"Joe Jones"); ERROR 1062 (23000): Duplicate entry '3' for key 'PRIMARY' MariaDB [cs4010]> insert into student_athlete (name) values ("Joe Jones"); Query OK, 1 row affected, 1 warning (0.00 sec) MariaDB [cs4010]> select * from student_athlete; +------------+-----------+--------+------+----------+ | student_id | name | year | test | sport | +------------+-----------+--------+------+----------+ | 0 | Joe Jones | NULL | NULL | | | 3 | Sam Smith | Junior | 90 | Baseball | +------------+-----------+--------+------+----------+ 2 rows in set (0.00 sec) MariaDB [cs4010]> alter table student_athlete modify student_id int NOT NULL AUTO_INCREMENT; Query OK, 2 rows affected (0.00 sec) Records: 2 Duplicates: 0 Warnings: 0 MariaDB [cs4010]> describe student_athlete; +------------+--------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +------------+--------------+------+-----+---------+----------------+ | student_id | int(11) | NO | PRI | NULL | auto_increment | | name | varchar(255) | NO | | NULL | | | year | varchar(20) | YES | | NULL | | | test | int(11) | YES | | NULL | | | sport | varchar(255) | NO | | NULL | | +------------+--------------+------+-----+---------+----------------+ 5 rows in set (0.00 sec) MariaDB [cs4010]> select * from student_athlete; +------------+-----------+--------+------+----------+ | student_id | name | year | test | sport | +------------+-----------+--------+------+----------+ | 1 | Joe Jones | NULL | NULL | | | 3 | Sam Smith | Junior | 90 | Baseball | +------------+-----------+--------+------+----------+ 2 rows in set (0.00 sec) MariaDB [cs4010]> insert into student_athlete (name) values ("Joe Java"); Query OK, 1 row affected, 1 warning (0.00 sec) MariaDB [cs4010]> select * from student_athlete; +------------+-----------+--------+------+----------+ | student_id | name | year | test | sport | +------------+-----------+--------+------+----------+ | 1 | Joe Jones | NULL | NULL | | | 3 | Sam Smith | Junior | 90 | Baseball | | 4 | Joe Java | NULL | NULL | | +------------+-----------+--------+------+----------+ 3 rows in set (0.00 sec) MariaDB [cs4010]>