sqlboiler/README.md

SQLBoiler

SQLBoiler is a tool to generate a Go data model tailored to your database schema.

It is a "database-first" ORM as opposed to "code-first" (like gorm/gorp). That means you must first create your database schema. Please use something like goose or some other migration tool to manage this part of the database's lifecycle.

Why?

Well...

About SQL Boiler

Features

• Full model generation
• High performance through generation
• Extremely fast code generation
• Uses boil.Executor (simple interface, sql.DB, sqlx.DB etc. compatible)
• Easy workflow (models can always be regenerated, full auto-complete)
• Strongly typed querying (usually no converting or binding to pointers)
• Hooks (Before/After Create/Select/Update/Delete/Upsert)
• Automatic CreatedAt/UpdatedAt
• Relationships/Associations
• Eager loading (recursive)
• Transactions
• Raw SQL fallbacks
• Compatibility tests (Run against your own DB schema)
• Debug logging

Supported Databases

• PostgreSQL

Note: Seeking contributors for other database engines.

A Small Taste

For a comprehensive list of available operations and examples please see Features & Examples.

import (
  // Import this so we don't have to use qm.Limit etc.
  . "github.com/vattle/sqlboiler/boil/qm"
)

// Open handle to database like normal
db, err := sql.Open("postgres", "dbname=fun user=abc")
if err != nil {
  return err
}

// Query all users
users, err := models.Users(db).All()

// Panic-able if you like to code that way
users := models.Users(db).AllP()

// More complex query
users, err := models.Users(db, Where("age > ?", 30), Limit(5), Offset(6)).All()

// Ultra complex query
users, err := models.Users(db,
  Select("id", "name"),
  InnerJoin("credit_cards c on c.user_id = users.id"),
  Where("age > ?", 30),
  AndIn("c.kind in ?", "visa", "mastercard"),
  Or("email like ?", "%aol.com%"),
  GroupBy("id", "name"),
  Having("count(c.id) > ?", 2),
  Limit(5),
  Offset(6),
).All()

// Use any "boil.Executor" implementation (*sql.DB, *sql.Tx, data-dog mock db)
// for any query.
tx, err := db.Begin()
if err != nil {
  return err
}
users, err := models.Users(tx).All()

// Relationships
user, err := models.Users(db).One()
if err != nil {
  return err
}
movies, err := user.FavoriteMovies(db).All()

// Eager loading
users, err := models.Users(db, Load("FavoriteMovies")).All()
if err != nil {
  return err
}
fmt.Println(len(users.R.FavoriteMovies))

Requirements & Pro Tips

Requirements

• Table names and column names should use snake_case format.
  • At the moment we require snake_case table names and column names. This is a recommended default in Postgres. We can reassess this for future database drivers.
• Join tables should use a composite primary key.
  • For join tables to be used transparently for relationships your join table must have a composite primary key that encompasses both foreign table foreign keys. For example, on a join table named user_videos you should have: primary key(user_id, video_id), with both user_id and video_id being foreign key columns to the users and videos tables respectively.

Pro Tips

• Foreign key column names should end with _id.
  • Foreign key column names in the format x_id will generate clearer method names. It is advisable to use this naming convention whenever it makes sense for your database schema.
• If you never plan on using the hooks functionality you can disable generation of this feature using the --no-hooks flag. This will save you some binary size.

Getting started

Download

go get -u -t github.com/vattle/sqlboiler

Configuration

Create a configuration file. Because the project uses viper, TOML, JSON and YAML are all supported. Environment variables are also able to be used. We will assume TOML for the rest of the documentation.

The configuration file should be named sqlboiler.toml and is searched for in the following directories in this order:

• ./
• $XDG_CONFIG_HOME/sqlboiler/
• $HOME/.config/sqlboiler/

We require you pass in the postgres configuration via the configuration file rather than env vars. There is no command line argument support for database configuration. Values given under the postgres block are passed directly to the pq driver. Here is a rundown of all the different values that can go in that section:

Name	Required	Default
dbname	yes	none
host	yes	none
port	no	5432
user	yes	none
pass	no	none
sslmode	no	"require"

You can also pass in these top level configuration values if you would prefer not to pass them through the command line or environment variables:

Name	Default
basedir	none
pkgname	"models"
output	"models"
exclude	[ ]
debug	false
no-hooks	false
no-auto-timestamps	false

Example:

[postgres]
dbname="dbname"
host="localhost"
port=5432
user="dbusername"
pass="dbpassword"

Initial Generation

After creating a configuration file that points at the database we want to generate models for, we can invoke the sqlboiler command line utility.

SQL Boiler generates a Go ORM from template files, tailored to your database schema.
Complete documentation is available at http://github.com/vattle/sqlboiler

Usage:
  sqlboiler [flags] <driver>

Examples:
sqlboiler postgres

Flags:
  -b, --basedir string        The base directory templates and templates_test folders are
  -d, --debug                 Debug mode prints stack traces on error
  -x, --exclude stringSlice   Tables to be excluded from the generated package (default [])
      --no-auto-timestamps    Disable automatic timestamps for created_at/updated_at
      --no-hooks              Disable hooks feature for your models
  -o, --output string         The name of the folder to output to (default "models")
  -p, --pkgname string        The name you wish to assign to your generated package (default "models")

Follow the steps below to do some basic model generation. Once we've generated our models, we can run the compatibility tests which will exercise the entirety of the generated code. This way we can ensure that our database is compatible with sqlboiler. If you find there are some failing tests, please check the Diagnosing Problems section.

# Generate our models and exclude the migrations table
sqlboiler -x goose_migrations postgres

# Run the generated tests
go test ./models # This requires an administrator postgres user because of some
                 # voodoo we do to disable triggers for the generated test db

Diagnosing Problems

The most common causes of problems and panics are:

• Forgetting to exclude tables you do not want included in your generation, like migration tables.
• Tables without a primary key. All tables require one.
• Forgetting foreign key constraints on your columns that reference other tables.
• The compatibility tests that run against your own DB schema require a superuser, ensure the user supplied in your config has adequate privileges.
• A nil or closed database handle. Ensure your passed in boil.Executor is not nil.
  • If you decide to use the G variant of functions instead, make sure you've initialized your global database handle using boil.SetDB().

For errors with other causes, it may be simple to debug yourself by looking at the generated code. Setting boil.DebugMode to true can help with this. You can change the output using boil.DebugWriter (defaults to os.Stdout).

If you're still stuck and/or you think you've found a bug, feel free to leave an issue and we'll do our best to help you.

Features & Examples

Most examples in this section will be demonstrated using the following schema, structs and variables:

CREATE TABLE pilots (
  id integer NOT NULL,
  name text NOT NULL,
);

ALTER TABLE pilots ADD CONSTRAINT pilot_pkey PRIMARY KEY (id);

CREATE TABLE jets (
  id integer NOT NULL,
  pilot_id integer NOT NULL,
  name text NOT NULL,
);

ALTER TABLE jets ADD CONSTRAINT jet_pkey PRIMARY KEY (id);
ALTER TABLE jets ADD CONSTRAINT pilots_fkey FOREIGN KEY (pilot_id) REFERENCES pilots(id);

CREATE TABLE languages (
  id integer NOT NULL,
  language text NOT NULL
);

ALTER TABLE languages ADD CONSTRAINT language_pkey PRIMARY KEY (id);

-- Join table
CREATE TABLE pilot_languages (
  pilot_id integer NOT NULL,
  language_id integer NOT NULL
);

-- Composite primary key
ALTER TABLE pilot_languages ADD CONSTRAINT pilot_language_pkey PRIMARY KEY (pilot_id, language_id);
ALTER TABLE pilot_languages ADD CONSTRAINT pilots_fkey FOREIGN KEY (pilot_id) REFERENCES pilots(id);
ALTER TABLE pilot_languages ADD CONSTRAINT languages_fkey FOREIGN KEY (language_id) REFERENCES languages(id);

The generated model structs for this schema look like the following. Note that I've included the relationship structs as well so you can see how it all pieces together, but these are unexported and not something you should ever need to touch directly:

type Pilot struct {
  ID   int    `boil:"id" json:"id" toml:"id" yaml:"id"`
  Name string `boil:"name" json:"name" toml:"name" yaml:"name"`

  R *pilotR `boil:"-" json:"-" toml:"-" yaml:"-"`
}

type pilotR struct {
  Licenses  LicenseSlice
  Languages LanguageSlice
  Jets      JetSlice
}

type Jet struct {
  ID      int    `boil:"id" json:"id" toml:"id" yaml:"id"`
  PilotID int    `boil:"pilot_id" json:"pilot_id" toml:"pilot_id" yaml:"pilot_id"`
  Name    string `boil:"name" json:"name" toml:"name" yaml:"name"`

  R *jetR `boil:"-" json:"-" toml:"-" yaml:"-"`
}

type jetR struct {
  Pilot *Pilot
}

type Language struct {
  ID       int    `boil:"id" json:"id" toml:"id" yaml:"id"`
  Language string `boil:"language" json:"language" toml:"language" yaml:"language"`

  R *languageR `boil:"-" json:"-" toml:"-" yaml:"-"`
}

type languageR struct {
  Pilots PilotSlice
}

// Open handle to database like normal
db, err := sql.Open("postgres", "dbname=fun user=abc")
if err != nil {
  return err
}

Query Building

We generate "Starter" methods for you. These methods are named as the plural versions of your model, for example: models.Jets(). Starter methods are used to build queries using our Query Mod System. They take a collection of Query Mods as parameters, and end with a call to a Finisher method.

Here are a few examples:

// SELECT COUNT(*) FROM pilots;
count, err := models.Pilots().Count()

// SELECT * FROM "pilots" LIMIT 5;
pilots, err := models.Pilots(qm.Limit(5)).All()

// DELETE FROM "pilots" WHERE "id"=$1;
err := models.Pilots(qm.Where("id=?", 1)).DeleteAll() 

As you can see, Query Mods allow you to modify your queries, and Finishers allow you to execute the final action.

Query Mod System

The query mod system allows you to modify queries created with Starter methods when performing query building. Here is a list of all of your generated query mods using examples:

// Dot import so we can access query mods directly instead of prefixing with "qm."
import . "github.com/vattle/sqlboiler/boil/qm"

// Use a raw query against a generated struct (Pilot in this example)
// If this query mod exists in your call, it will override the others.
// "?" placeholders are not supported here, use "$1, $2" etc.
SQL("select * from pilots where id=$1", 10)
models.Pilots(SQL("select * from pilots where id=$1", 10)).All()

Select("id", "name") // Select specific columns.
From("pilots as p") // Specify the FROM table manually, can be useful for doing complex queries.

// WHERE clause building
Where("name=?", "John")
And("age=?", 24)
Or("height=?", 183)

// WHERE IN clause building
WhereIn("name, age in ?", "John" 24, "Tim", 33) // Generates: WHERE ("name","age") IN (($1,$2),($3,$4))
AndIn("weight in ?", 84)
OrIn("height in ?", 183, 177, 204)

InnerJoin("pilots p on jets.pilot_id=?", 10)

GroupBy("name")
OrderBy("age, height")

Having("count(jets) > 2")

Limit(15)
Offset(5)

// Explicit locking
For("update nowait")

// Eager Loading -- Load takes the relationship name, ie the struct field name of the 
// Relationship struct field you want to load.
Load("Languages") // If it's a ToOne relationship it's in singular form, ToMany is plural.

Note: We don't force you to break queries apart like this if you don't want to, the following is also valid and supported by query mods that take a clause:

Where("(name=? OR age=?) AND height=?", "John", 24, 183)

Function Variations

You will find that most functions have the following variations. We've used the Delete method to demonstrate:

// Set the global db handle for G method variants.
boil.SetDB(db)

pilot, _ := models.PilotFind(db, 1)

err := pilot.Delete(db) // Regular variant, takes a db handle (boil.Executor interface).
pilot.DeleteP(db)       // Panic variant, takes a db handle and panics on error. 
err := pilot.DeleteG()  // Global variant, uses the globally set db handle (boil.SetDB()).
pilot.DeleteGP()        // Global&Panic variant, combines the global db handle and panic on error.

Note that it's slightly different for the query building starters----...

Automatic CreatedAt/UpdatedAt

If your generated SQLBoiler models package can find columns with the names created_at or updated_at it will automatically set them to time.Now() in your database, and update your object appropriately. To disable this feature use --no-auto-timestamps.

Note: You can set the timezone for this feature by calling boil.SetLocation()

Overriding Automatic Timestamps

• Insert
  • Timestamps for both updated_at and created_at that are zero values will be set automatically.
  • To set the timestamp to null, set Valid to false and Time to a non-zero value. This is somewhat of a work around until we can devise a better solution in a later version.
• Update
  • The updated_at column will always be set to time.Now(). If you need to override this value you will need to fall back to another method in the meantime: boil.SQL(), overriding updated_at in all of your objects using a hook, or create your own wrapper.
• Upsert
  • created_at will be set automatically if it is a zero value, otherwise your supplied value will be used. To set created_at to null, set Valid to false and Time to a non-zero value.
  • The updated_at column will always be set to time.Now().

Hooks

Finishers

Raw Query

Binding

Transactions

Debug Logging

Select

Find

Insert

Update

updateall slice and query

Delete

deleteall slice and query

Upsert

Reload

reloadall slice

Relationships

relationships to one and to many relationship set ops (to one: set, remove, tomany: add, set, remove) eager loading (nested and flat)

Benchmarks

FAQ

Won't compiling models for a huge database be very slow?

No, because Go's toolchain - unlike traditional toolchains - makes the compiler do most of the work instead of the linker. This means that when the first go install is done it can take a little bit of time because there is a lot of code that is generated. However, because of this work balance between the compiler and linker in Go, linking to that code afterwards in the subsequent compiles is extremely fast.