# Simple and performant client for PostgreSQL, MySQL, and SQLite
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[![PkgGoDev](https://pkg.go.dev/badge/github.com/uptrace/bun)](https://pkg.go.dev/github.com/uptrace/bun)
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**Status**: API freeze (stable release). Note that all sub-packages (mainly extra/\* packages) are
not part of the API freeze and are developed independently. You can think of them as 3-rd party
packages that share one repo with the core.
Main features are:
- Works with [PostgreSQL](https://bun.uptrace.dev/guide/drivers.html#postgresql),
[MySQL](https://bun.uptrace.dev/guide/drivers.html#mysql) (including MariaDB),
[SQLite](https://bun.uptrace.dev/guide/drivers.html#sqlite).
- [Selecting](/example/basic/) into a map, struct, slice of maps/structs/vars.
- [Bulk inserts](https://bun.uptrace.dev/guide/queries.html#insert).
- [Bulk updates](https://bun.uptrace.dev/guide/queries.html#update) using common table expressions.
- [Bulk deletes](https://bun.uptrace.dev/guide/queries.html#delete).
- [Fixtures](https://bun.uptrace.dev/guide/fixtures.html).
- [Migrations](https://bun.uptrace.dev/guide/migrations.html).
- [Soft deletes](https://bun.uptrace.dev/guide/soft-deletes.html).
Resources:
- [Examples](https://github.com/uptrace/bun/tree/master/example)
- [Documentation](https://bun.uptrace.dev/)
- [Reference](https://pkg.go.dev/github.com/uptrace/bun)
- [Starter kit](https://github.com/go-bun/bun-starter-kit)
- [RealWorld app](https://github.com/go-bun/bun-realworld-app)
github.com/frederikhors/orm-benchmark results
```
4000 times - Insert
raw_stmt: 0.38s 94280 ns/op 718 B/op 14 allocs/op
raw: 0.39s 96719 ns/op 718 B/op 13 allocs/op
beego_orm: 0.48s 118994 ns/op 2411 B/op 56 allocs/op
bun: 0.57s 142285 ns/op 918 B/op 12 allocs/op
pg: 0.58s 145496 ns/op 1235 B/op 12 allocs/op
gorm: 0.70s 175294 ns/op 6665 B/op 88 allocs/op
xorm: 0.76s 189533 ns/op 3032 B/op 94 allocs/op
4000 times - MultiInsert 100 row
raw: 4.59s 1147385 ns/op 135155 B/op 916 allocs/op
raw_stmt: 4.59s 1148137 ns/op 131076 B/op 916 allocs/op
beego_orm: 5.50s 1375637 ns/op 179962 B/op 2747 allocs/op
bun: 6.18s 1544648 ns/op 4265 B/op 214 allocs/op
pg: 7.01s 1753495 ns/op 5039 B/op 114 allocs/op
gorm: 9.52s 2379219 ns/op 293956 B/op 3729 allocs/op
xorm: 11.66s 2915478 ns/op 286140 B/op 7422 allocs/op
4000 times - Update
raw_stmt: 0.26s 65781 ns/op 773 B/op 14 allocs/op
raw: 0.31s 77209 ns/op 757 B/op 13 allocs/op
beego_orm: 0.43s 107064 ns/op 1802 B/op 47 allocs/op
bun: 0.56s 139839 ns/op 589 B/op 4 allocs/op
pg: 0.60s 149608 ns/op 896 B/op 11 allocs/op
gorm: 0.74s 185970 ns/op 6604 B/op 81 allocs/op
xorm: 0.81s 203240 ns/op 2994 B/op 119 allocs/op
4000 times - Read
raw: 0.33s 81671 ns/op 2081 B/op 49 allocs/op
raw_stmt: 0.34s 85847 ns/op 2112 B/op 50 allocs/op
beego_orm: 0.38s 94777 ns/op 2106 B/op 75 allocs/op
pg: 0.42s 106148 ns/op 1526 B/op 22 allocs/op
bun: 0.43s 106904 ns/op 1319 B/op 18 allocs/op
gorm: 0.65s 162221 ns/op 5240 B/op 108 allocs/op
xorm: 1.13s 281738 ns/op 8326 B/op 237 allocs/op
4000 times - MultiRead limit 100
raw: 1.52s 380351 ns/op 38356 B/op 1037 allocs/op
raw_stmt: 1.54s 385541 ns/op 38388 B/op 1038 allocs/op
pg: 1.86s 465468 ns/op 24045 B/op 631 allocs/op
bun: 2.58s 645354 ns/op 30009 B/op 1122 allocs/op
beego_orm: 2.93s 732028 ns/op 55280 B/op 3077 allocs/op
gorm: 4.97s 1241831 ns/op 71628 B/op 3877 allocs/op
xorm: doesn't work
```
## Installation
```go
go get github.com/uptrace/bun
```
You also need to install a database/sql driver and the corresponding Bun
[dialect](https://bun.uptrace.dev/guide/drivers.html).
## Quickstart
First you need to create a `sql.DB`. Here we are using the
[sqliteshim](https://pkg.go.dev/github.com/uptrace/bun/driver/sqliteshim) driver which chooses
between [modernc.org/sqlite](https://modernc.org/sqlite/) and
[mattn/go-sqlite3](https://github.com/mattn/go-sqlite3) depending on your platform.
```go
import "github.com/uptrace/bun/driver/sqliteshim"
sqldb, err := sql.Open(sqliteshim.ShimName, "file::memory:?cache=shared")
if err != nil {
panic(err)
}
```
And then create a `bun.DB` on top of it using the corresponding SQLite
[dialect](https://bun.uptrace.dev/guide/drivers.html) that comes with Bun:
```go
import (
"github.com/uptrace/bun"
"github.com/uptrace/bun/dialect/sqlitedialect"
)
db := bun.NewDB(sqldb, sqlitedialect.New())
```
Now you are ready to issue some queries:
```go
type User struct {
ID int64
Name string
}
user := new(User)
err := db.NewSelect().
Model(user).
Where("name != ?", "").
OrderExpr("id ASC").
Limit(1).
Scan(ctx)
```
The code above is equivalent to:
```go
query := "SELECT id, name FROM users AS user WHERE name != '' ORDER BY id ASC LIMIT 1"
rows, err := sqldb.QueryContext(ctx, query)
if err != nil {
panic(err)
}
if !rows.Next() {
panic(sql.ErrNoRows)
}
user := new(User)
if err := db.ScanRow(ctx, rows, user); err != nil {
panic(err)
}
if err := rows.Err(); err != nil {
panic(err)
}
```
## Basic example
To provide initial data for our [example](/example/basic/), we will use Bun
[fixtures](https://bun.uptrace.dev/guide/fixtures.html):
```go
import "github.com/uptrace/bun/dbfixture"
// Register models for the fixture.
db.RegisterModel((*User)(nil), (*Story)(nil))
// WithRecreateTables tells Bun to drop existing tables and create new ones.
fixture := dbfixture.New(db, dbfixture.WithRecreateTables())
// Load fixture.yaml which contains data for User and Story models.
if err := fixture.Load(ctx, os.DirFS("."), "fixture.yaml"); err != nil {
panic(err)
}
```
The `fixture.yaml` looks like this:
```yaml
- model: User
rows:
- _id: admin
name: admin
emails: ['admin1@admin', 'admin2@admin']
- _id: root
name: root
emails: ['root1@root', 'root2@root']
- model: Story
rows:
- title: Cool story
author_id: '{{ $.User.admin.ID }}'
```
To select all users:
```go
users := make([]User, 0)
if err := db.NewSelect().Model(&users).OrderExpr("id ASC").Scan(ctx); err != nil {
panic(err)
}
```
To select a single user by id:
```go
user1 := new(User)
if err := db.NewSelect().Model(user1).Where("id = ?", 1).Scan(ctx); err != nil {
panic(err)
}
```
To select a story and the associated author in a single query:
```go
story := new(Story)
if err := db.NewSelect().
Model(story).
Relation("Author").
Limit(1).
Scan(ctx); err != nil {
panic(err)
}
```
To select a user into a map:
```go
m := make(map[string]interface{})
if err := db.NewSelect().
Model((*User)(nil)).
Limit(1).
Scan(ctx, &m); err != nil {
panic(err)
}
```
To select all users scanning each column into a separate slice:
```go
var ids []int64
var names []string
if err := db.NewSelect().
ColumnExpr("id, name").
Model((*User)(nil)).
OrderExpr("id ASC").
Scan(ctx, &ids, &names); err != nil {
panic(err)
}
```
For more details, please consult [docs](https://bun.uptrace.dev/) and check [examples](example).
## Contributors
Thanks to all the people who already contributed!