Tables Without Primary Keys
Learn how to add primary keys to your tables and why they’re essential for data replication.
Why Primary Keys Matter 🔑
Primary keys are crucial for data replication because they:
- Ensure Data Ordering: We use primary keys as partition keys in Kafka to guarantee the correct sequence of operations
- Maintain Data Integrity: Primary keys enable reliable
MERGEoperations to keep your data consistent
Adding Primary Keys: Two Common Scenarios 🛠️
Scenario 1: Using Existing Unique Columns
Scenario 1: Using Existing Unique Columns
Let’s say you have a users_no_pk table with a unique email field:
To make this table replication-ready, simply promote the unique email to a primary key:
Scenario 2: Adding a New Primary Key Column
Scenario 2: Adding a New Primary Key Column
For tables without any unique identifiers, we can add a new primary key column. Let’s use this example:
Current table contents:
Add a new primary key column:
After adding the primary key:
💡 Pro Tip: Your application code doesn’t need any changes! You can continue inserting data without specifying the primary key:
Need Help? 🤝
Have questions about adding primary keys to your tables? Reach out to us at [email protected]!