Install MySQL driver: Execute go get -u github.com/go-sql-driver/mysql; 2. Use the database/sql package to establish a connection with DSN (such as username:password@tcp(localhost:3306)/dbname), and verify the connection through db.Ping(); 3. It is recommended to configure connection pool parameters such as SetMaxOpenConns, SetMaxIdleConns and SetConnMaxLifetime to optimize performance; 4. Use db.Query to read data with rows.Scan when executing queries; 5. Pay attention to common problems: Make sure the database exists, the username and password are correct, and use an underscore prefix when importing the driver to trigger initialization. The complete process includes importing drivers, building DSNs, opening databases, testing connections, executing queries and properly handling errors, and successfully connecting and operating the MySQL database.
Connecting to a MySQL database in Go is straightforward using the database/sql package and a MySQL driver like go-sql-driver/mysql . Below is a practical example showing how to set up and use a connection.
? 1. Install the MySQL Driver
First, install the MySQL driver:
go get -u github.com/go-sql-driver/mysql
? 2. Basic Connection Example
Here's a simple Go program that connects to a MySQL database and pings it to verify the connection:
package main
import (
"database/sql"
"fmt"
"log"
_ "github.com/go-sql-driver/mysql" // Import the MySQL driver
)
func main() {
// Replace with your actual connection details
dsn := "username:password@tcp(localhost:3306)/your_database_name"
db, err := sql.Open("mysql", dsn)
if err != nil {
log.Fatal("Failed to open database:", err)
}
defer db.Close()
// Test the connection
err = db.Ping()
if err != nil {
log.Fatal("Failed to ping database:", err)
}
fmt.Println("Connected to MySQL database!")
}? Key Details
DSN (Data Source Name) : The string
username:password@tcp(localhost:3306)/dbnameis the DSN.- Use
tcp(localhost:3306)for local connections. - You can add parameters like
parseTime=trueif you're working with time fields:dsn := "username:password@tcp(localhost:3306)/your_db?parseTime=true"
- Use
sql.Opendoesn't connect immediately — it just initializes the database handle.
db.Ping()actually tests the connection.
? 3. Using Connection Settings (Optional but Recommended)
For production, configure connection pooling:
db.SetMaxOpenConns(25) db.SetMaxIdleConns(25) db.SetConnMaxLifetime(time.Minute * 5)
These help avoid resource exhaustion and improve performance.
? 4. Example Query
Once connected, you can run queries:
var id int
var name string
rows, err := db.Query("SELECT id, name FROM users")
if err != nil {
log.Fatal(err)
}
defer rows.Close()
for rows.Next() {
err := rows.Scan(&id, &name)
if err != nil {
log.Fatal(err)
}
fmt.Printf("ID: %d, Name: %s\n", id, name)
}?? Common Issues
- "Unknown database" : Make sure the database exists.
- "Access denied" : Check username, password, and MySQL user privileges.
- Driver not found : Ensure you imported the driver with
_ "github.com/go-sql-driver/mysql"— the underscore is cruel.
Basically, that's all you need to get started. The pattern is:
- Import driver
- Build DSN
-
sql.Open -
db.Ping - Use
dbfor queries
Not complicated — just pay attention to the DSN format and error handling.
The above is the detailed content of go by example connecting to a mysql database. For more information, please follow other related articles on the PHP Chinese website!
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