PostgresDB 23503: Foreign key violation

When a foreign key constraint is violated.
  1. Identify the Error Details: Check the error message to identify which foreign key constraint was violated (the message typically mentions the constraint name and the table). For example, if the error is something like ERROR: insert or update on table "orders" violates foreign key constraint "orders_customer_id_fkey", it means the violation occurred on orders table with the orders_customer_id_fkey constraint.
  2. Review the Foreign Key Constraint: Query the information_schema to review the details of the foreign key constraint. Replace your_constraint_name with the actual constraint name identified in step 1.
  3. SELECT *
    FROM information_schema.table_constraints
    WHERE constraint_name = 'your_constraint_name';
  4. Check the Referenced Table and Column: Based on the information from step 2, identify which table and column the foreign key is referencing. This information is crucial to understand what value is missing or incorrect in the referencing table.
  5. Compare Data in Both Tables: Now that you know the tables and columns involved, compare the data to find mismatches. For example, if your foreign key is customer_id in the orders table referencing id in the customers table, check if the customer_id you are trying to insert/update in orders exists in customers.
  6. SELECT *
    FROM referenced_table
    WHERE id NOT IN (SELECT distinct foreign_key_column FROM referencing_table);
  7. Replace referenced_table, id, foreign_key_column, and referencing_table with your actual table names and column names.
  8. Correct the Data: If the investigation shows that the data being inserted or updated does not have a corresponding foreign key in the referenced table, correct the data. This might mean inserting the missing record into the referenced table or correcting the foreign key value being inserted/updated in the referencing table.
  9. Retry the Operation: After correcting the data, retry the operation that caused the foreign key violation error.

This immediate action plan focuses on diagnosing and fixing the specific issue causing the foreign key violation error in a Postgres database, assuming no database administrator is available to assist.

Master

PostgresDB

in Minutes — Grab the Ultimate Cheatsheet

(Perfect for DevOps & SREs)

Most-used commands
Real-world configs/examples
Handy troubleshooting shortcuts
Your email is safe with us. No spam, ever.

Thankyou for your submission

We have sent the cheatsheet on your email!
Oops! Something went wrong while submitting the form.

PostgresDB

Cheatsheet

(Perfect for DevOps & SREs)

Most-used commands
Your email is safe with us. No spam, ever.

Thankyou for your submission

We have sent the cheatsheet on your email!
Oops! Something went wrong while submitting the form.

MORE ISSUES

Made with ❤️ in Bangalore & San Francisco 🏢

Doctor Droid