How to add foreign keys in phpmyadmin

Adding a foreign key in phpMyAdmin can be achieved by following these steps: Select the parent table that contains the foreign key. Edit the parent table structure and add new columns in "Columns". Enable foreign key constraints and select the referencing table and key. Set update/delete operations. save Changes.

How to add foreign keys in phpMyAdmin

In MySQL, foreign keys are used to create two tables relationship between. In phpMyAdmin, you can add a foreign key by following these steps:

1. Select the parent table

• In phpMyAdmin, navigate to the parent table that contains the foreign key .

2. Edit the parent table structure

• Click the "Structure" tab of the table.

3. Add a new column

• In the Columns section, click the Add Column button at the bottom of the table.

4. Set the data type

• Select the data type of the new column, usually INT or BIGINT, depending on the type of the foreign key column .

5. Enable foreign key constraints

• In the "Other" section, select the "Foreign Key" checkbox.

6. Select the reference table and key

• Select the table referenced by the foreign key from the "Reference Table" drop-down menu.
• Select the key column referenced by the foreign key from the "Reference Key" drop-down menu.

7. Set update/delete operation

• In the "Update" and "Delete" tabs, select the foreign key to be updated or deleted time operation. Typically, select Cascade Update and Cascade Delete.

8. Save changes

• Click the Save button to apply the changes.

Note:

• Ensure that the column data type in the parent table matches the foreign key column data type in the reference table.
• Before adding a foreign key, ensure that the key column in the reference table has been created.
• If you add a foreign key to an existing table, you may need to rebuild the table in phpMyAdmin to activate the constraint.

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