GORM正式支持数据库MySQL、PostgreSQL、SQLite、SQL Server
MySQL
import (
"gorm.io/driver/mysql"
"gorm.io/gorm"
)
func main() {
// refer https://github.com/go-sql-driver/mysql#dsn-data-source-name for details
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 handletime.Timecorrectly, you need to includeparseTimeas a parameter. (more parameters)
To fully support UTF-8 encoding, you need to changecharset=utf8tocharset=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", // data source name
DefaultStringSize: 256, // default size for string fields
DisableDatetimePrecision: true, // disable datetime precision, which not supported before MySQL 5.6
DontSupportRenameIndex: true, // drop & create when rename index, rename index not supported before MySQL 5.7, MariaDB
DontSupportRenameColumn: true, // `change` when rename column, rename column not supported before MySQL 8, MariaDB
SkipInitializeWithVersion: false, // auto configure based on currently MySQL version
}), &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",
|
// data source name, refer https://github.com/go-sql-driver/mysql#dsn-data-source-name }), &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:
// https://github.com/go-gorm/postgres
db, err := gorm.Open(postgres.New(postgres.Config{
DSN: "user=gorm password=gorm dbname=gorm port=9920 sslmode=disable TimeZone=Asia/Shanghai",
PreferSimpleProtocol: true, // disables implicit prepared statement usage
}), &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{})
|
SQLite
import (
"gorm.io/driver/sqlite" // Sqlite driver based on GGO
// "github.com/glebarez/sqlite"
"gorm.io/gorm"
)
// github.com/mattn/go-sqlite3
db, err := gorm.Open(sqlite.Open("gorm.db"), &gorm.Config{})
|
// Pure go SQLite driver, checkout https://github.com/glebarez/sqlite for details
NOTE: You can also use
file::memory:?cache=sharedinstead 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"
)
// github.com/denisenkom/go-mssqldb
dsn := "sqlserver://gorm:LoremIpsum86@localhost:9930?database=gorm"
db, err := gorm.Open(sqlserver.Open(dsn), &gorm.Config{})
|
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{})
// Auto Migrate
db.AutoMigrate(&User{})
// Set table options
db.Set("gorm:table_options", "ENGINE=Distributed(cluster, default, hits)").AutoMigrate(&User{})
// Insert
db.Create(&user)
// Select
db.Find(&user, "id = ?", 10)
// Batch Insert
var users = []User{user1, user2, user3}
db.Create(&users)
// ...
}
|
Connection Pool
GORM using database/sql to maintain connection pool
sqlDB, err := db.DB() // SetMaxIdleConns sets the maximum number of connections in the idle connection pool. sqlDB.SetMaxIdleConns(10) // SetMaxOpenConns sets the maximum number of open connections to the database. sqlDB.SetMaxOpenConns(100) // SetConnMaxLifetime sets the maximum amount of time a connection may be reused. sqlDB.SetConnMaxLifetime(time.Hour) |
有关详细信息，请参阅通用接口
不支持的数据库
有些数据库可能与mysql或postgres方言兼容，在这种情况下，您可以使用这些数据库的方言。
- 登录 发表评论