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# Go-MySQL-Driver A MySQL-Driver for Go's [database/sql](https://golang.org/pkg/database/sql/) package  --------------------------------------- * [Features](#features) * [Requirements](#requirements) * [Installation](#installation) * [Usage](#usage) * [DSN (Data Source Name)](#dsn-data-source-name) * [Password](#password) * [Protocol](#protocol) * [Address](#address) * [Parameters](#parameters) * [Examples](#examples) * [Connection pool and timeouts](#connection-pool-and-timeouts) * [context.Context Support](#contextcontext-support) * [ColumnType Support](#columntype-support) * [LOAD DATA LOCAL INFILE support](#load-data-local-infile-support) * [time.Time support](#timetime-support) * [Unicode support](#unicode-support) * [Testing / Development](#testing--development) * [License](#license) --------------------------------------- ## Features * Lightweight and [fast](https://github.com/go-sql-driver/sql-benchmark "golang MySQL-Driver performance") * Native Go implementation. No C-bindings, just pure Go * Connections over TCP/IPv4, TCP/IPv6, Unix domain sockets or [custom protocols](https://godoc.org/github.com/go-sql-driver/mysql#DialFunc) * Automatic handling of broken connections * Automatic Connection Pooling *(by database/sql package)* * Supports queries larger than 16MB * Full [`sql.RawBytes`](https://golang.org/pkg/database/sql/#RawBytes) support. * Intelligent `LONG DATA` handling in prepared statements * Secure `LOAD DATA LOCAL INFILE` support with file allowlisting and `io.Reader` support * Optional `time.Time` parsing * Optional placeholder interpolation ## Requirements * Go 1.18 or higher. We aim to support the 3 latest versions of Go. * MySQL (5.6+), MariaDB, Percona Server, Google CloudSQL or Sphinx (2.2.3+) --------------------------------------- ## Installation Simple install the package to your [$GOPATH](https://github.com/golang/go/wiki/GOPATH "GOPATH") with the [go tool](https://golang.org/cmd/go/ "go command") from shell: ```bash $ go get -u github.com/go-sql-driver/mysql ``` Make sure [Git is installed](https://git-scm.com/downloads) on your machine and in your system's `PATH`. ## Usage _Go MySQL Driver_ is an implementation of Go's `database/sql/driver` interface. You only need to import the driver and can use the full [`database/sql`](https://golang.org/pkg/database/sql/) API then. Use `mysql` as `driverName` and a valid [DSN](#dsn-data-source-name) as `dataSourceName`: ```go import ( "database/sql" "time" _ "github.com/go-sql-driver/mysql" ) // ... db, err := sql.Open("mysql", "user:password@/dbname") if err != nil { panic(err) } // See "Important settings" section. db.SetConnMaxLifetime(time.Minute * 3) db.SetMaxOpenConns(10) db.SetMaxIdleConns(10) ``` [Examples are available in our Wiki](https://github.com/go-sql-driver/mysql/wiki/Examples "Go-MySQL-Driver Examples"). ### Important settings `db.SetConnMaxLifetime()` is required to ensure connections are closed by the driver safely before connection is closed by MySQL server, OS, or other middlewares. Since some middlewares close idle connections by 5 minutes, we recommend timeout shorter than 5 minutes. This setting helps load balancing and changing system variables too. `db.SetMaxOpenConns()` is highly recommended to limit the number of connection used by the application. There is no recommended limit number because it depends on application and MySQL server. `db.SetMaxIdleConns()` is recommended to be set same to `db.SetMaxOpenConns()`. When it is smaller than `SetMaxOpenConns()`, connections can be opened and closed much more frequently than you expect. Idle connections can be closed by the `db.SetConnMaxLifetime()`. If you want to close idle connections more rapidly, you can use `db.SetConnMaxIdleTime()` since Go 1.15. ### DSN (Data Source Name) The Data Source Name has a common format, like e.g. [PEAR DB](http://pear.php.net/manual/en/package.database.db.intro-dsn.php) uses it, but without type-prefix (optional parts marked by squared brackets): ``` [username[:password]@][protocol[(address)]]/dbname[?param1=value1&...&paramN=valueN] ``` A DSN in its fullest form: ``` username:password@protocol(address)/dbname?param=value ``` Except for the databasename, all values are optional. So the minimal DSN is: ``` /dbname ``` If you do not want to preselect a database, leave `dbname` empty: ``` / ``` This has the same effect as an empty DSN string: ``` ``` `dbname` is escaped by [PathEscape()](https://pkg.go.dev/net/url#PathEscape) since v1.8.0. If your database name is `dbname/withslash`, it becomes: ``` /dbname%2Fwithslash ``` Alternatively, [Config.FormatDSN](https://godoc.org/github.com/go-sql-driver/mysql#Config.FormatDSN) can be used to create a DSN string by filling a struct. #### Password Passwords can consist of any character. Escaping is **not** necessary. #### Protocol See [net.Dial](https://golang.org/pkg/net/#Dial) for more information which networks are available. In general you should use a Unix domain socket if available and TCP otherwise for best performance. #### Address For TCP and UDP networks, addresses have the form `host[:port]`. If `port` is omitted, the default port will be used. If `host` is a literal IPv6 address, it must be enclosed in square brackets. The functions [net.JoinHostPort](https://golang.org/pkg/net/#JoinHostPort) and [net.SplitHostPort](https://golang.org/pkg/net/#SplitHostPort) manipulate addresses in this form. For Unix domain sockets the address is the absolute path to the MySQL-Server-socket, e.g. `/var/run/mysqld/mysqld.sock` or `/tmp/mysql.sock`. #### Parameters *Parameters are case-sensitive!* Notice that any of `true`, `TRUE`, `True` or `1` is accepted to stand for a true boolean value. Not surprisingly, false can be specified as any of: `false`, `FALSE`, `False` or `0`. ##### `allowAllFiles` ``` Type: bool Valid Values: true, false Default: false ``` `allowAllFiles=true` disables the file allowlist for `LOAD DATA LOCAL INFILE` and allows *all* files. [*Might be insecure!*](https://dev.mysql.com/doc/refman/8.0/en/load-data.html#load-data-local) ##### `allowCleartextPasswords` ``` Type: bool Valid Values: true, false Default: false ``` `allowCleartextPasswords=true` allows using the [cleartext client side plugin](https://dev.mysql.com/doc/en/cleartext-pluggable-authentication.html) if required by an account, such as one defined with the [PAM authentication plugin](http://dev.mysql.com/doc/en/pam-authentication-plugin.html). Sending passwords in clear text may be a security problem in some configurations. To avoid problems if there is any possibility that the password would be intercepted, clients should connect to MySQL Server using a method that protects the password. Possibilities include [TLS / SSL](#tls), IPsec, or a private network. ##### `allowFallbackToPlaintext` ``` Type: bool Valid Values: true, false Default: false ``` `allowFallbackToPlaintext=true` acts like a `--ssl-mode=PREFERRED` MySQL client as described in [Command Options for Connecting to the Server](https://dev.mysql.com/doc/refman/5.7/en/connection-options.html#option_general_ssl-mode) ##### `allowNativePasswords` ``` Type: bool Valid Values: true, false Default: true ``` `allowNativePasswords=false` disallows the usage of MySQL native password method. ##### `allowOldPasswords` ``` Type: bool Valid Values: true, false Default: false ``` `allowOldPasswords=true` allows the usage of the insecure old password met