Connect a Golang application to OceanBase Database (using Go-SQL-Driver/MySQL)

This topic provides a code example on how to connect a Golang application to OceanBase Database.

Install the Golang driver

Use the go get command (for Go V1.13 - V1.16)

Run the following command to install the Golang driver:

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

Note: For details about Go-SQL-Driver/MySQL, see GitHub.

Use the go install command

If the go get command cannot be used due to version or network reasons, you can try the following:

1. Clone the go-sql-driver/mysql repository in GitHub to the src directory.

   cd /usr/local/go/src   
   git clone https://github.com/go-sql-driver/mysql.git 
   

   Note: In some versions, the default directory for go install may not be /src, so you can determine the actual directory by the error reported after go install is executed. For example, if the error is cannot find package "mysql" in: /usr/local/go/src/vendor/mysql, then put the mysql folder in the /src/vendor directory before running the install command.

2. Run the following command to install the Golang driver:

   go install mysql
   

Connect to OceanBase Database

Run the following sample code to connect to OceanBase Database, where you can use username:password@protocol(address)/dbname?param=value to set the connection string.

package main

···

import (
    "database/sql"
    "fmt"
    "log"
    
    _ "github.com/go-sql-driver/mysql" //Fill in the exact path for installing go-sql-driver/mysql. If installed in the src directory, you can fill in "mysql".
)

type City struct {
    Id         int
    Name       string
    Population int
}

func select_all() {
    conn := "root:@tcp(127.0.0.1:2881)/testdb"
    db, err := sql.Open("mysql", conn)
    if err != nil {
        log.Fatal(err)
    }
    
    defer db.Close()
    
    if err != nil {
        log.Fatal(err)
    }
    
    res, err := db.Query("SELECT * FROM cities")
    if err != nil {
        log.Fatal(err)
    }
    
    defer res.Close()
    
    if err != nil {
        log.Fatal(err)
    }
    
    for res.Next() {
        
        var city City
        err := res.Scan(&city.Id, &city.Name, &city.Population)
        
        if err != nil {
            log.Fatal(err)
        }
        
        fmt.Printf("%v\n", city)
    }
}

Troubleshoot the PreparedStatement error

Log on to OceanBase Database as the root user and run the following command:

alter system set _ob_enable_prepared_statement = true;