AnalyticDB:Go

Prerequisites

• Git is installed and its path is added to the Path environment variable.
• Go is downloaded and installed. For more information, see Download and install.
• Go MySQL Driver is installed.
  1. Download Go MySQL Driver from go-sql-driver/mysql.
  2. Use the go tool in the shell script to install the package to $GOPATH.

     go get github.com/go-sql-driver/mysql

Connect to an AnalyticDB for MySQL cluster

package main
import (
    "database/sql"
    "fmt"
    _ "github.com/go-sql-driver/mysql"
)
const (
   // user: the account used to connect to the AnalyticDB for MySQL cluster. AnalyticDB for MySQL offers the following types of accounts: privileged accounts and standard accounts. 
    user = "adb_test"
    // password: the password of the account used to connect to the AnalyticDB for MySQL cluster. 
    password = "xxx"
    // host: the IP address of the AnalyticDB for MySQL cluster. You can obtain the IP address on the Cluster Information page in the AnalyticDB for MySQL console. 
    host = "127.0.xx.xx"
    // 3306: the port used to connect to the AnalyticDB for MySQL cluster. 
    port = 3306
    // database: the name of the database in the AnalyticDB for MySQL cluster. 
    database = "database_name"
    // connectTimeout: the timeout period of the database connection. 
    connectTimeout = "10s"
)
func main() {
    // Enable the database connection. 
    url := fmt.Sprintf("%s:%s@tcp(%s:%d)/%s?timeout=%s", user, password, host, port, database, connectTimeout)
    db, err := sql.Open("mysql", url)
    if err != nil {
        panic(err.Error())
    }
    // Set the maximum number of enabled connections. The default value is 0, which indicates that no limit applies to the maximum number of enabled connections. 
    db.SetMaxOpenConns(2)
    // Set the maximum number of idle connections. 
    db.SetMaxIdleConns(1)
    // Set the maximum duration of connections. By default, no limit applies to the duration of connections, and connections are always kept alive. 
    // This setting cannot ensure that connections in the connection pool are persistent for a full hour. 
    // This setting is not about the timeout period for idle connections. A connection expires one hour after it is created for the first time. 
    // Theoretically, a shorter maximum duration of connections indicates a higher frequency of creating connections from scratch. 
    db.SetConnMaxLifetime(time.Hour)
    // defer the close till after the main function has finished
    // executing
    defer db.Close()
    rows, err := db.Query("show tables")
    if err != nil {
        panic(err.Error())
    }
    for rows.Next() {
        var tableName string
        err := rows.Scan(&tableName)
        if err != nil {
            panic(err.Error())
        }
        fmt.Println(tableName)
    }
}

Enable a prepared statement for a server

package main
import (
    "database/sql"
    "fmt"
    _ "github.com/go-sql-driver/mysql"
    "time"
)
const (
   // user: the account used to connect to the AnalyticDB for MySQL cluster. AnalyticDB for MySQL offers the following types of accounts: privileged accounts and standard accounts. 
    user = "adb_test"
    // password: the password of the account used to connect to the AnalyticDB for MySQL cluster. 
    password = "xxx"
    // host: the IP address of the AnalyticDB for MySQL cluster. You can obtain the IP address on the Cluster Information page in the AnalyticDB for MySQL console. 
    host = "127.0.xx.xx"
    // 3306: the port used to connect to the AnalyticDB for MySQL cluster. 
    port = 3306
    // database: the name of the database in the AnalyticDB for MySQL cluster. 
    database = "database_name"
    // connectTimeout: the timeout period of the database connection. 
    connectTimeout = "10s"
)
func main() {
    // open the database connection
    url := fmt.Sprintf("%s:%s@tcp(%s:%d)/%s?timeout=%s", user, password, host, port, database, connectTimeout)
    db, err := sql.Open("mysql", url)
    if err != nil {
        panic(err.Error())
    }
    // Set the maximum number of enabled connections. The default value is 0, which indicates that no limit applies to the maximum number of enabled connections. 
    db.SetMaxOpenConns(2)
    // Set the maximum number of idle connections.
    db.SetMaxIdleConns(1)
    // Set the maximum duration of connections. By default, no limit applies to the duration of connections, and connections are always kept alive. 
    // This setting cannot ensure that connections in the connection pool are persistent for a full hour. A connection may become unavailable and be automatically closed due to some reasons. 
    // This setting is not about the timeout period for idle connections. A connection does not expire after it becomes idle for one hour, but expires one hour after it is created for the first time. 
    // Theoretically, a shorter maximum duration of connections indicates a higher frequency of creating connections from scratch. 
    db.SetConnMaxLifetime(time.Hour)
    defer db.Close()
    stmt, err := db.Prepare("select * from student where id = ?")
    if err != nil {
        panic(err.Error())
    }
    defer stmt.Close()
    rows, err := stmt.Query(9)
    if err != nil {
        panic(err.Error())
    }
    defer rows.Close()
    for rows.Next() {
        var id string
        var name string
        var unit string
        err := rows.Scan(&id, &name, &unit)
        if err != nil {
            panic(err.Error())
        }
        fmt.Println(fmt.Sprintf("%s, %s, %s", id, name, unit))
    }
}

Enable a prepare statement for a client

package main
import (
    "database/sql"
    "fmt"
    _ "github.com/go-sql-driver/mysql"
    "time"
)
const (
    // user: the account used to connect to the AnalyticDB for MySQL cluster. AnalyticDB for MySQL offers the following types of accounts: privileged accounts and standard accounts. 
    user = "adb_test"
    // password: the password of the account used to connect to the AnalyticDB for MySQL cluster. 
    password = "xxx"
    // host: the IP address of the AnalyticDB for MySQL cluster. You can obtain the IP address on the Cluster Information page in the AnalyticDB for MySQL console. 
    host = "127.0.xx.xx"
    // 3306: the port used to connect to the AnalyticDB for MySQL cluster. 
    port = 3306
    // database: the name of the database in the AnalyticDB for MySQL cluster. 
    database = "database_name"
    // connectTimeout: the timeout period of the database connection. 
    connectTimeout = "10s"
)
func main() {
    // Enable the database connection. 
    url := fmt.Sprintf("%s:%s@tcp(%s:%d)/%s?timeout=%s&interpolateParams=true", user, password, host, port, database, connectTimeout)
    db, err := sql.Open("mysql", url)
    if err != nil {
        panic(err.Error())
    }
    // Set the maximum number of enabled connections. The default value is 0, which indicates that no limit applies to the maximum number of enabled connections. 
    db.SetMaxOpenConns(2)
    // Set the maximum number of idle connections. 
    db.SetMaxIdleConns(1)
    // Set the maximum duration of connections. By default, no limit applies to the duration of connections, and connections are always kept alive. 
    // This setting cannot ensure that connections in the connection pool are persistent for a full hour. A connection may become unavailable and be automatically closed due to some reasons. 
    // This setting is not about the timeout period for idle connections. A connection does not expire after it becomes idle for one hour, but expires one hour after it is created for the first time. 
    // Theoretically, a shorter maximum duration of connections indicates a higher frequency of creating connections from scratch. 
    db.SetConnMaxLifetime(time.Hour)
    defer db.Close()
    rows, err := db.Query("select * from student where id = ?", 9)
    if err != nil {
        panic(err.Error())
    }
    defer rows.Close()
    for rows.Next() {
        var id string
        var name string
        var unit string
        err := rows.Scan(&id, &name, &unit)
        if err != nil {
            panic(err.Error())
        }
        fmt.Println(fmt.Sprintf("%s, %s, %s", id, name, unit))
    }
}