Database agnostic ORM for Go!
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Hood is a database agnostic ORM for Go developed by @eaignr. It was written with following points in mind:

  • Chainable API
  • Transaction support
  • Database dialect interface
  • No implicit fields
  • Clean and testable codebase

Dialects currently supported

Adding a dialect is as simple as copying the original pg.go, replacing the statement and field values with the new dialect versions.




If the dialect is registered, you can open the database directly using

hd, err := hood.Open("postgres", "user=<username> dbname=<database>")

or you can pass an existing database and dialect to hood.New(*sql.DB, hood.Dialect)

hd, err := hood.New(db, &Postgres{})


Schemas can be declared using the following syntax (only for demonstration purposes, would not produce valid SQL since it has 2 primary keys)

type Person struct {
	// Auto-incrementing int field 'id'
	Id hood.Id

	// Custom primary key field 'first_name', with presence validation
	FirstName string `sql:"pk" validate:"presence"`

	// Varchar field 'last_name' with size 128, NOT NULL
	LastName hood.VarChar `sql:"size(128),notnull"`

	// Varchar field 'tag' with size 255, default value 'customer'
	Tag hood.VarChar `sql:"default('customer')"`

	// You can also combine tags, default value 'orange'
	CombinedTags hood.VarChar `sql:"size(128),default('orange')"`
	Updated      time.Time    // timestamp field 'updated'
	Data         []byte       // data field 'data'
	IsAdmin      bool         // boolean field 'is_admin'
	Notes        string       // text field 'notes'

	// Validates number range
	Balance int `validate:"range(10:20)"`

	// ... and other built in types (int, uint, float...)

Schema creation is completely optional, you can use any other tool you like.


Besides the sql: struct tag, you can specify a validate: tag for model validation:

  • presence: validates that a field is set
  • len(min:max): validates that a string or VarChar field has a specified min or max length. You can also omit values if you just want a min or max limit like so len(min:), however the : is always required!
  • range(min:max): validates that an int value lies in the specific range, or has a specified min or max value (e.g. for max only range(:max))

You can also chain validations, e.g. validate:"len(:12),presence"


package main

import (

func main() {
	// Open a DB connection, use New() alternatively for unregistered dialects
	hd, err := hood.Open("postgres", "user=hood dbname=hood_test sslmode=disable")
	if err != nil {

	// Create a table
	type Fruit struct {
		Id    hood.Id
		Name  string `validate:"presence"`
		Color string

	err = hd.CreateTable(&Fruit{})
	if err != nil {

	fruits := []Fruit{
		Fruit{Name: "banana", Color: "yellow"},
		Fruit{Name: "apple", Color: "red"},
		Fruit{Name: "grapefruit", Color: "yellow"},
		Fruit{Name: "grape", Color: "green"},
		Fruit{Name: "pear", Color: "yellow"},

	// Start a transaction
	tx := hd.Begin()

	ids, err := tx.SaveAll(&fruits)
	if err != nil {

	fmt.Println("inserted ids:", ids) // [1 2 3 4 5]

	// Commit changes
	err = tx.Commit()
	if err != nil {

	// Ids are automatically updated
	if fruits[0].Id != 1 || fruits[1].Id != 2 || fruits[2].Id != 3 {
		panic("id not set")

	// If an id is already set, a call to save will result in an update
	fruits[0].Color = "green"

	ids, err = hd.SaveAll(&fruits)
	if err != nil {

	fmt.Println("updated ids:", ids) // [1 2 3 4 5]

	if fruits[0].Id != 1 || fruits[1].Id != 2 || fruits[2].Id != 3 {
		panic("id not set")

	// Let's try to save a row that does not satisfy the required validations
	_, err = hd.Save(&Fruit{})
	if err == nil || err.Error() != "value not set" {
		panic("does not satisfy validations, should not save")

	// Find
	// The markers are db agnostic, so you can always use '?'
	// e.g. in Postgres they are replaced with $1, $2, ...
	var results []Fruit
	err = hd.Where("color = ?", "green").OrderBy("name").Limit(1).Find(&results)
	if err != nil {

	fmt.Println("results:", results) // [{1 banana green}]

	// Delete
	ids, err = hd.DeleteAll(&results)
	if err != nil {

	fmt.Println("deleted ids:", ids) // [1]

	results = nil
	err = hd.Find(&results)
	if err != nil {

	fmt.Println("results:", results) // [{2 apple red} {3 grapefruit yellow} {4 grape green} {5 pear yellow}]

	// Drop