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+# 5.2 MySQL
+
+The LAMP stack has been very popular on the internet in recent years, and the M in LAMP stand for MySQL. MySQL is famous because it's open source and easy to use. As such, it has become the de-facto database in the back-ends of many websites.
+
+## MySQL drivers
+
+There are a couple of drivers that support MySQL in Go. Some of them implement the `database/sql` interface, and others use their own interface standards.
+
+- [https://github.com/go-sql-driver/mysql](https://github.com/go-sql-driver/mysql) supports `database/sql`, written in pure Go.
+- [https://github.com/ziutek/mymysql](https://github.com/ziutek/mymysql) supports `database/sql` and user defined interfaces, written in pure Go.
+
+I'll use the first driver in the following examples (I use this one in my personal projects too), and I also recommend that you use it for the following reasons:
+
+- It's a new database driver and supports more features.
+- It fully supports `database/sql` interface standards.
+- Supports keep-alive, long connections with thread-safety.
+
+## Samples
+
+In the following sections, I'll use the same database table structure for different databases, then create SQL as follows:
+```sql
+	CREATE TABLE `userinfo` (
+	    `uid` INT(10) NOT NULL AUTO_INCREMENT,
+	    `username` VARCHAR(64) NULL DEFAULT NULL,
+	    `department` VARCHAR(64) NULL DEFAULT NULL,
+	    `created` DATE NULL DEFAULT NULL,
+	    PRIMARY KEY (`uid`)
+	);
+```	
+The following example shows how to operate on a database based on the `database/sql` interface standards.
+```Go
+	package main
+	
+	import (
+	    _ "github.com/go-sql-driver/mysql"
+	    "database/sql"
+	    "fmt"
+	)
+	
+	func main() {
+	    db, err := sql.Open("mysql", "astaxie:astaxie@/test?charset=utf8")
+	    checkErr(err)
+	
+	    // insert
+	    stmt, err := db.Prepare("INSERT userinfo SET username=?,department=?,created=?")
+	    checkErr(err)
+	
+	    res, err := stmt.Exec("astaxie", "研发部门", "2012-12-09")
+	    checkErr(err)
+	
+	    id, err := res.LastInsertId()
+	    checkErr(err)
+	
+	    fmt.Println(id)
+	    // update
+	    stmt, err = db.Prepare("update userinfo set username=? where uid=?")
+	    checkErr(err)
+	
+	    res, err = stmt.Exec("astaxieupdate", id)
+	    checkErr(err)
+	
+	    affect, err := res.RowsAffected()
+	    checkErr(err)
+	
+	    fmt.Println(affect)
+	
+	    // query
+	    rows, err := db.Query("SELECT * FROM userinfo")
+	    checkErr(err)
+	
+	    for rows.Next() {
+	        var uid int
+	        var username string
+	        var department string
+	        var created string
+	        err = rows.Scan(&uid, &username, &department, &created)
+	        checkErr(err)
+	        fmt.Println(uid)
+	        fmt.Println(username)
+	        fmt.Println(department)
+	        fmt.Println(created)
+	    }
+	    
+	    rows.Close()
+	
+	    // delete
+	    stmt, err = db.Prepare("delete from userinfo where uid=?")
+	    checkErr(err)
+	
+	    res, err = stmt.Exec(id)
+	    checkErr(err)
+	
+	    affect, err = res.RowsAffected()
+	    checkErr(err)
+	
+	    fmt.Println(affect)
+	
+	    db.Close()
+	
+	}
+	
+	func checkErr(err error) {
+	    if err != nil {
+	        panic(err)
+	    }
+	}
+```
+Let me explain a few of the important functions here:
+
+- `sql.Open()` opens a registered database driver. The Go-MySQL-Driver registered the mysql driver here. The second argument is the DSN (Data Source Name) that defines information pertaining to the database connection. It supports following formats:
+
+		user@unix(/path/to/socket)/dbname?charset=utf8
+		user:password@tcp(localhost:5555)/dbname?charset=utf8
+		user:password@/dbname
+		user:password@tcp([de:ad:be:ef::ca:fe]:80)/dbname
+
+- `db.Prepare()` returns a SQL operation that is going to be executed. It also returns the execution status after executing SQL.
+- `db.Query()` executes SQL and returns a Rows result.
+- `stmt.Exec()` executes SQL that has been prepared and stored in Stmt.
+
+Note that we use the format `=?` to pass arguments. This is necessary for preventing SQL injection attacks.
+
+## Links
+
+- [Directory](preface.md)
+- Previous section: [database/sql interface](05.1.md)
+- Next section: [SQLite](05.3.md)