Javascript TypeORM Encountering the 'NoVersionOrUpdateDateColumnError' when using TypeORM with optimistic locking.
Understanding TypeORM and Its Purpose
TypeORM is a popular Object-Relational Mapper (ORM) for TypeScript and JavaScript (ES6, ES7, ES8) that allows developers to interact with databases using object-oriented programming principles. It supports various databases such as MySQL, PostgreSQL, SQLite, and more. TypeORM is designed to work in Node.js and can be used with TypeScript or JavaScript.
One of the key features of TypeORM is its support for advanced database functionalities, including transactions, migrations, and various types of locking mechanisms, such as optimistic locking.
Identifying the Symptom: NoVersionOrUpdateDateColumnError
When working with TypeORM, you may encounter the following error message: NoVersionOrUpdateDateColumnError. This error typically occurs when you attempt to use optimistic locking in your application, but the necessary version or update date column is not defined in your entity.
Explaining the NoVersionOrUpdateDateColumnError
The NoVersionOrUpdateDateColumnError is thrown by TypeORM when it detects that optimistic locking is enabled on an entity, but it cannot find a column to track versioning or update timestamps. Optimistic locking is a technique used to prevent concurrent updates from overwriting each other by checking a version or timestamp before committing changes.
For more details on optimistic locking, you can refer to the TypeORM documentation on optimistic locking.
Steps to Fix the NoVersionOrUpdateDateColumnError
Step 1: Define a Version Column
To resolve this error, you need to define a version column in your entity. This can be done using the @VersionColumn decorator. Here is an example:
import { Entity, PrimaryGeneratedColumn, Column, VersionColumn } from 'typeorm';
@Entity()
export class User {
@PrimaryGeneratedColumn()
id: number;
@Column()
name: string;
@VersionColumn()
version: number;
}
In this example, the @VersionColumn decorator is used to define a version column that TypeORM will automatically manage for optimistic locking.
Step 2: Define an Update Date Column
Alternatively, you can use an update date column to track changes. This can be done using the @UpdateDateColumn decorator:
import { Entity, PrimaryGeneratedColumn, Column, UpdateDateColumn } from 'typeorm';
@Entity()
export class User {
@PrimaryGeneratedColumn()
id: number;
@Column()
name: string;
@UpdateDateColumn()
updatedAt: Date;
}
Here, the @UpdateDateColumn automatically updates the timestamp whenever the entity is updated.
Step 3: Verify Entity Configuration
Ensure that your entity is correctly configured and that the version or update date column is properly defined. Double-check your entity files for any syntax errors or missing decorators.
Conclusion
By defining either a version column or an update date column, you can resolve the NoVersionOrUpdateDateColumnError and effectively use optimistic locking in your TypeORM application. For further reading, you can explore the TypeORM Entities Documentation for more information on entity configuration and decorators.
Try DrDroid: AI Agent for Debugging
Try DrDroid: AI Agent for Fixing Production Errors
MORE ISSUES
Backed by
