Select from MySQL Table A That Does Not Exist in Table B

You can use IN operator to select from one table that does not exist in another. To understand the above syntax, let us create a table.

The first table name is A and second table name is B. The query to create a table is as follows

mysql> create table A
   -> (
   -> Value int
   -> );
Query OK, 0 rows affected (0.56 sec)

Now you can insert some records in the table using insert command.

The query is as follows

mysql> insert into A values(10);
Query OK, 1 row affected (0.23 sec)
mysql> insert into A values(20);
Query OK, 1 row affected (0.11 sec)
mysql> insert into A values(30);
Query OK, 1 row affected (0.11 sec)
mysql> insert into A values(50);
Query OK, 1 row affected (0.10 sec)
mysql> insert into A values(80);
Query OK, 1 row affected (0.12 sec)

Display all records from the table using select statement.

The query is as follows

mysql> select *from A;

The following is the output

+-------+
| Value |
+-------+
| 10    |
| 20    |
| 30    |
| 50    |
| 80    |
+-------+
5 rows in set (0.00 sec)

Here is the query to create second table with the name B

mysql> create table B
   -> (
   -> Value2 int
   -> );
Query OK, 0 rows affected (0.65 sec)

Insert some records in the table using insert command.

The query is as follows

mysql> insert into B values(20);
Query OK, 1 row affected (0.11 sec)
mysql> insert into B values(50);
Query OK, 1 row affected (0.15 sec)

Now you can display all records from the table using select statement.

The query is as follows

mysql> select *from B;

The following is the output

+--------+
| Value2 |
+--------+
| 20     |
| 50     |
+--------+
2 rows in set (0.00 sec)

Here is the query to select from table A which does not exist in table B

mysql> SELECT * FROM A WHERE Value NOT IN (SELECT Value2 FROM B);

The following is the output

+-------+
| Value |
+-------+
| 10    |
| 30    |
| 80    |
+-------+
3 rows in set (0.00 sec)