# Incremental data replication - Manual confirm（Optional）

+ On `MySQL instance1` and `instance2`

```
mysql> SELECT * FROM salesdb.sales;
+----+-------+------+
| id | pname | cnt  |
+----+-------+------+
|  1 | book  |  100 |
+----+-------+------+
1 row in set (0.00 sec)

mysql> INSERT INTO salesdb.sales VALUES(3,'shoes',120);
Query OK, 1 row affected (0.01 sec)

mysql> SELECT * FROM salesdb.sales;
+----+-------+------+
| id | pname | cnt  |
+----+-------+------+
|  1 | book  |  100 |
|  3 | shoes |  120 |
+----+-------+------+
2 rows in set (0.00 sec)
```

```
mysql> select * from sales;
+----+-------+------+
| id | pname | cnt  |
+----+-------+------+
|  2 | cup   |  200 |
+----+-------+------+
1 row in set (0.00 sec)

mysql> insert into sales values(4, 'tea', 79);
Query OK, 1 row affected (0.01 sec)

mysql> select * from sales;
+----+-------+------+
| id | pname | cnt  |
+----+-------+------+
|  2 | cup   |  200 |
|  4 | tea   |   79 |
+----+-------+------+
2 rows in set (0.00 sec)
```
-------------------------------------------------------------
We separately insert data into the 'salesdb.sales' table in two `MySQL` instances of the upstream database in order to observe if the incremental replication is successful. Note: If it is production data, please do not perform this operation!

```
mysql> SELECT * FROM salesdb.sales;
+----+-------+------+
| id | pname | cnt  |
+----+-------+------+
|  1 | book  |  100 |
+----+-------+------+
1 row in set (0.00 sec)

mysql> INSERT INTO salesdb.sales VALUES(3,'shoes',120);
Query OK, 1 row affected (0.01 sec)

mysql> SELECT * FROM salesdb.sales;
+----+-------+------+
| id | pname | cnt  |
+----+-------+------+
|  1 | book  |  100 |
|  3 | shoes |  120 |
+----+-------+------+
2 rows in set (0.00 sec)


mysql> select * from sales;
+----+-------+------+
| id | pname | cnt  |
+----+-------+------+
|  2 | cup   |  200 |
+----+-------+------+
1 row in set (0.00 sec)

mysql> insert into sales values(4, 'tea', 79);
Query OK, 1 row affected (0.01 sec)

mysql> select * from sales;
+----+-------+------+
| id | pname | cnt  |
+----+-------+------+
|  2 | cup   |  200 |
|  4 | tea   |   79 |
+----+-------+------+
2 rows in set (0.00 sec)
```