The insert statement conflicts with the foreign key constraint

When we use the insert statement to insert data into a table containing foreign key constraints, we may encounter conflict problems.

The function of a foreign key is to ensure that the value in one column must correspond to a specific value in another table. Therefore, if you try to insert a value into one table that does not exist in another table, you will cause a foreign key constraint violation. That's why the insert operation fails.

In order to solve this problem, there are two main methods:

1. Insert a value that satisfies the constraint

Please ensure that all foreign keys must be in the corresponding A matching record exists in the table. For example, when you add a new order to the order table, you need to first ensure that the customer to which the order belongs actually exists in the customer table.

2. Cancel the foreign key constraint

If you cannot insert matching records in the corresponding table, you can cancel the foreign key constraint. However, this may have other side effects. For example, canceling the constraint of d's foreign key may cause dirty data to appear on the associated table. In addition, it can easily break the integrity and security of the database. Therefore, it is recommended to use the second method only in special cases and not as the first choice.

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