📊 Tables (POC not for production)

Type-safe PostgreSQL schema to Go code generator

Transform your PostgreSQL database schemas into elegant, type-safe Go code with zero boilerplate.

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✨ Features

• 🔒 Type Safety - Generate strongly-typed Go aliases from PostgreSQL columns
• 🚀 Zero Boilerplate - Automatic code generation with minimal configuration
• 📦 Package Organization - Clean, structured output with proper Go conventions
• 🎯 Column Mapping - Easy-to-use column name constants for query building
• 🔄 Incremental Updates - Regenerate only when schema changes
• 🛡️ Null Safety - Proper handling of nullable columns with pointer types

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🚀 Quick Start

Installation

go install github.com/mymyka/tables/cmd/tables@latest

Basic Usage

tables --db "host=localhost port=5432 user=postgres password=postgres dbname=mydb sslmode=disable" --output gen/tables

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📖 How It Works

Input: PostgreSQL Schema

CREATE TABLE users (
    id              SERIAL PRIMARY KEY,
    username        VARCHAR(50) NOT NULL,
    first_name      VARCHAR(100) NOT NULL,
    last_name       VARCHAR(100) NOT NULL,
    created_at      TIMESTAMP DEFAULT CURRENT_TIMESTAMP NOT NULL,
    email           VARCHAR(100) NOT NULL UNIQUE,
    google_user_id  VARCHAR(100) UNIQUE,
    hashed_password VARCHAR(255)
);

Output: Type-Safe Go Code

package users

import "time"

// Type aliases for compile-time safety
type Id = int32
type Username = string
type FirstName = string
type LastName = string
type CreatedAt = time.Time
type Email = string
type GoogleUserId = *string      // Nullable
type HashedPassword = *string    // Nullable

// Column name constants
type usersColumnNames struct {
    Id             string
    Username       string
    FirstName      string
    LastName       string
    CreatedAt      string
    Email          string
    GoogleUserId   string
    HashedPassword string
}

var C = usersColumnNames{
    Id:             "id",
    Username:       "username",
    FirstName:      "first_name",
    LastName:       "last_name",
    CreatedAt:      "created_at",
    Email:          "email",
    GoogleUserId:   "google_user_id",
    HashedPassword: "hashed_password",
}

var Table = "users"

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💡 Usage Examples

Building Models

import "your-project/gen/tables/users"

type UserModel struct {
    Id        users.Id
    Username  users.Username
    FirstName users.FirstName
    LastName  users.LastName
    Email     users.Email
    CreatedAt users.CreatedAt
}

Type-Safe Queries

// Using column constants prevents typos
query := fmt.Sprintf(`
    SELECT %s, %s, %s 
    FROM %s 
    WHERE %s = $1
`, 
    users.C.Id, 
    users.C.Username, 
    users.C.Email,
    users.Table,
    users.C.Username,
)

// Type-safe scanning
var user UserModel
err := db.QueryRow(query, "john_doe").Scan(
    &user.Id,
    &user.Username, 
    &user.Email,
)

Working with Nullable Fields

// Nullable fields are properly typed as pointers
var googleId users.GoogleUserId
if user.GoogleUserId != nil {
    googleId = *user.GoogleUserId
}

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⚙️ Configuration

Command Line Options

Flag	Description	Required	Default
--db	PostgreSQL connection string	✅	-
--output	Output directory for generated code	✅	-
--exclude	Comma-separated list of tables to exclude	❌	-
--include	Comma-separated list of tables to include	❌	All tables
--package-prefix	Prefix for generated package names	❌	-

Connection String Format

host=localhost port=5432 user=username password=password dbname=database sslmode=disable

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🏗️ Project Structure

After running Tables, your project structure will look like:

your-project/
├── gen/
│   └── tables/
│       ├── users/
│       │   └── users.go
│       ├── orders/
│       │   └── orders.go
│       └── products/
│           └── products.go
├── main.go
└── go.mod

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🔧 Type Mapping

PostgreSQL Type	Go Type	Nullable Go Type
SERIAL, INTEGER	int32	*int32
BIGSERIAL, BIGINT	int64	*int64
VARCHAR, TEXT	string	*string
BOOLEAN	bool	*bool
TIMESTAMP	time.Time	*time.Time
DATE	time.Time	*time.Time
DECIMAL, NUMERIC	float64	*float64
UUID	string	*string
JSONB	[]byte	*[]byte

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🤝 Contributing

We welcome contributions! Please feel free to submit a Pull Request.

1. Fork the repository
2. Create your feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add some amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

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📝 License

This project is licensed under the MIT License - see the LICENSE file for details.

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🙏 Acknowledgments

• Inspired by the need for type-safe database interactions in Go
• Built with ❤️ for the Go community
• Special thanks to all contributors

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🌊 From Future Pirate King 🌊