Package com.example.demo.db

Class SchemaFixRunner

java.lang.Object

com.example.demo.db.SchemaFixRunner

All Implemented Interfaces:

org.springframework.boot.CommandLineRunner

@Component
public class SchemaFixRunner
extends Object
implements org.springframework.boot.CommandLineRunner

A one-time component designed to fix common database schema issues encountered when using JPA with certain database dilects, it uses alot of spring boots code so check their doc to learn more

Constructor Summary

Constructors

Constructor	Description
SchemaFixRunner(org.springframework.jdbc.core.JdbcTemplate jdbc)	Constructs the SchemaFixRunner and injects the necessary JdbcTemplate.

Method Summary

Modifier and Type	Method	Description
void	run(String... args)	Executes the schema fix logic when the Spring Boot application starts up.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

SchemaFixRunner

public SchemaFixRunner(org.springframework.jdbc.core.JdbcTemplate jdbc)

Constructs the SchemaFixRunner and injects the necessary JdbcTemplate.

Parameters:

jdbc - The Spring JDBC template.

Method Details

run

public void run(String... args)

Executes the schema fix logic when the Spring Boot application starts up.

The execution involves: 1. Checking the primary key status to skip if already AUTO_INCREMENT. 2. Identifying and dropping any existing foreign key constraints on the child table. 3. Dropping any residual indexes left behind after the foreign key removal. 4. Modifying the parent table's primary key (`id`) to be AUTO_INCREMENT. 5. Recreating the foreign key constraint on the child table, ensuring data integrity.

Specified by:

run in interface org.springframework.boot.CommandLineRunner

Parameters:

args - Command line arguments passed to the application.