GORM officially supports the databases MySQL, PostgreSQL, GaussDB, SQLite, SQL Server, and TiDB
MySQL import ( "gorm.io/driver/mysql" "gorm.io/gorm" ) func main () { dsn := "user:pass@tcp(127.0.0.1:3306)/dbname?charset=utf8mb4&parseTime=True&loc=Local" db, err := gorm.Open(mysql.Open(dsn), &gorm.Config{}) }
NOTE: To handle time.Time
correctly, you need to include parseTime
as a parameter. (more parameters ) To fully support UTF-8 encoding, you need to change charset=utf8
to charset=utf8mb4
. See this article for a detailed explanation
MySQL Driver provides a few advanced configurations which can be used during initialization, for example:
db, err := gorm.Open(mysql.New(mysql.Config{ DSN: "gorm:gorm@tcp(127.0.0.1:3306)/gorm?charset=utf8&parseTime=True&loc=Local" , DefaultStringSize: 256 , DisableDatetimePrecision: true , DontSupportRenameIndex: true , DontSupportRenameColumn: true , SkipInitializeWithVersion: false , }), &gorm.Config{})
Customize Driver GORM allows to customize the MySQL driver with the DriverName
option, for example:
import ( _ "example.com/my_mysql_driver" "gorm.io/driver/mysql" "gorm.io/gorm" ) db, err := gorm.Open(mysql.New(mysql.Config{ DriverName: "my_mysql_driver" , DSN: "gorm:gorm@tcp(localhost:9910)/gorm?charset=utf8&parseTime=True&loc=Local" , }), &gorm.Config{})
Existing database connection GORM allows to initialize *gorm.DB
with an existing database connection
import ( "database/sql" "gorm.io/driver/mysql" "gorm.io/gorm" ) sqlDB, err := sql.Open("mysql" , "mydb_dsn" ) gormDB, err := gorm.Open(mysql.New(mysql.Config{ Conn: sqlDB, }), &gorm.Config{})
PostgreSQL import ( "gorm.io/driver/postgres" "gorm.io/gorm" ) dsn := "host=localhost user=gorm password=gorm dbname=gorm port=9920 sslmode=disable TimeZone=Asia/Shanghai" db, err := gorm.Open(postgres.Open(dsn), &gorm.Config{})
We are using pgx as postgres’s database/sql driver, it enables prepared statement cache by default, to disable it:
db, err := gorm.Open(postgres.New(postgres.Config{ DSN: "user=gorm password=gorm dbname=gorm port=9920 sslmode=disable TimeZone=Asia/Shanghai" , PreferSimpleProtocol: true , }), &gorm.Config{})
Customize Driver GORM allows to customize the PostgreSQL driver with the DriverName
option, for example:
import ( _ "github.com/GoogleCloudPlatform/cloudsql-proxy/proxy/dialers/postgres" "gorm.io/gorm" ) db, err := gorm.Open(postgres.New(postgres.Config{ DriverName: "cloudsqlpostgres" , DSN: "host=project:region:instance user=postgres dbname=postgres password=password sslmode=disable" , })
Existing database connection GORM allows to initialize *gorm.DB
with an existing database connection
import ( "database/sql" "gorm.io/driver/postgres" "gorm.io/gorm" ) sqlDB, err := sql.Open("pgx" , "mydb_dsn" ) gormDB, err := gorm.Open(postgres.New(postgres.Config{ Conn: sqlDB, }), &gorm.Config{})
GaussDB import ( "gorm.io/driver/gaussdb" "gorm.io/gorm" ) dsn := "host=localhost user=gorm password=gorm dbname=gorm port=8000 sslmode=disable TimeZone=Asia/Shanghai" db, err := gorm.Open(gaussdb.Open(dsn), &gorm.Config{})
We are using gaussdb-go as gaussdb’s database/sql driver, it enables prepared statement cache by default, to disable it:
db, err := gorm.Open(gaussdb.New(gaussdb.Config{ DSN: "user=gorm password=gorm dbname=gorm port=8000 sslmode=disable TimeZone=Asia/Shanghai" , PreferSimpleProtocol: true , }), &gorm.Config{})
Customize Driver GORM allows to customize the GaussDB driver with the DriverName
option, for example:
import ( _ "github.com/GoogleCloudPlatform/cloudsql-proxy/proxy/dialers/gaussdb" "gorm.io/gorm" ) db, err := gorm.Open(gaussdb.New(gaussdb.Config{ DriverName: "cloudsqlgaussdb" , DSN: "host=project:region:instance user=gaussdb dbname=gaussdb password=password sslmode=disable" , })
Existing database connection GORM allows to initialize *gorm.DB
with an existing database connection
import ( "database/sql" "gorm.io/driver/gaussdb" "gorm.io/gorm" ) sqlDB, err := sql.Open("gaussdbgo" , "mydb_dsn" ) gormDB, err := gorm.Open(gaussdb.New(gaussdb.Config{ Conn: sqlDB, }), &gorm.Config{})
SQLite import ( "gorm.io/driver/sqlite" "gorm.io/gorm" ) db, err := gorm.Open(sqlite.Open("gorm.db" ), &gorm.Config{})
NOTE: You can also use file::memory:?cache=shared
instead of a path to a file. This will tell SQLite to use a temporary database in system memory. (See SQLite docs for this)
SQL Server import ( "gorm.io/driver/sqlserver" "gorm.io/gorm" ) dsn := "sqlserver://gorm:LoremIpsum86@localhost:9930?database=gorm" db, err := gorm.Open(sqlserver.Open(dsn), &gorm.Config{})
TiDB TiDB is compatible with MySQL protocol. You can follow the MySQL part to create a connection to TiDB.
There are some points noteworthy for TiDB:
You can use gorm:"primaryKey;default:auto_random()"
tag to use AUTO_RANDOM
feature for TiDB.
TiDB supported SAVEPOINT
from v6.2.0
, please notice the version of TiDB when you use this feature.
TiDB supported FOREIGN KEY
from v6.6.0
, please notice the version of TiDB when you use this feature.
import ( "fmt" "gorm.io/driver/mysql" "gorm.io/gorm" ) type Product struct { ID uint `gorm:"primaryKey;default:auto_random()"` Code string Price uint } func main () { db, err := gorm.Open(mysql.Open("root:@tcp(127.0.0.1:4000)/test" ), &gorm.Config{}) if err != nil { panic ("failed to connect database" ) } db.AutoMigrate(&Product{}) insertProduct := &Product{Code: "D42" , Price: 100 } db.Create(insertProduct) fmt.Printf("insert ID: %d, Code: %s, Price: %d\n" , insertProduct.ID, insertProduct.Code, insertProduct.Price) readProduct := &Product{} db.First(&readProduct, "code = ?" , "D42" ) fmt.Printf("read ID: %d, Code: %s, Price: %d\n" , readProduct.ID, readProduct.Code, readProduct.Price) }
Clickhouse https://github.com/go-gorm/clickhouse
import ( "gorm.io/driver/clickhouse" "gorm.io/gorm" ) func main () { dsn := "tcp://localhost:9000?database=gorm&username=gorm&password=gorm&read_timeout=10&write_timeout=20" db, err := gorm.Open(clickhouse.Open(dsn), &gorm.Config{}) db.AutoMigrate(&User{}) db.Set("gorm:table_options" , "ENGINE=Distributed(cluster, default, hits)" ).AutoMigrate(&User{}) db.Create(&user) db.Find(&user, "id = ?" , 10 ) var users = []User{user1, user2, user3} db.Create(&users) }
Connection Pool GORM using database/sql to maintain connection pool
sqlDB, err := db.DB() sqlDB.SetMaxIdleConns(10 ) sqlDB.SetMaxOpenConns(100 ) sqlDB.SetConnMaxLifetime(time.Hour)
Refer Generic Interface for details
Unsupported Databases Some databases may be compatible with the mysql
or postgres
dialect, in which case you could just use the dialect for those databases.
For others, you are encouraged to make a driver, pull request welcome!