GORM

Introduction to GORM

GORM is a powerful ORM library that is highly popular. It offers a wide range of features, including chainable queries, preloading, transactions, and model associations.

• Full-featured ORM
• Associations (Has One, Has Many, Belongs To, Many To Many, Polymorphism, Single Table Inheritance)
• Hooks for Create, Save, Update, Delete, and Find operations
• Support for preloading with Preload and Joins
• Transactions, nested transactions, Save Points, and Rollback To Saved Point
• Context, precompiled mode, and DryRun mode
• Batch inserts, FindInBatches, Find/Create with Map, CRUD using SQL expressions and Context Valuer
• SQL builder, Upsert, database locks, Optimizer/Index/Comment Hint, named parameters, subqueries
• Composite primary keys, indexes, constraints
• Automatic migrations
• Custom logger
• Flexible and extensible plugin API: Database Resolver (for multiple databases and read-write separation), Prometheus, and more
• Rigorously tested for each feature
• Developer-friendly

Pros and Cons

Pros:

• Powerful Features: GORM provides extensive functionality, such as chainable queries, preloading, transactions, and model associations.
• Ease of Use: GORM's API design is very developer-friendly, allowing developers to quickly get started.
• Flexibility: GORM offers numerous configuration options to tailor it to specific needs.

Cons:

• Performance: Due to heavy use of reflection, GORM's performance can be lower.
• Not as Convenient: GORM's API, while similar to writing raw SQL, doesn't significantly reduce the workload. Queries and updates still require struct definitions, and handling null values can be cumbersome.

Examples of Using GORM

Creating Data

db.Create(&User{Name: "Jinzhu", Age: 18})

Updating Data

db.Model(&user).Update("Age", 20)

Querying Data

db.First(&user, 1) // Retrieve user with ID 1

Deleting Data

db.Delete(&user)