Using PostgreSQL with Go
Description
In this tutorial, we will explore how to use PostgreSQL with Go, covering setup, connecting to a PostgreSQL database, and performing basic operations using the database/sql package and lib/pq driver.
Setup
Before starting, ensure you have Go installed on your system. Install the lib/pq package, which provides a PostgreSQL driver for Go:
go get github.com/lib/pq
Connecting to PostgreSQL
To connect to a PostgreSQL database in Go, use the following code snippet:
package main
import (
"database/sql"
"fmt"
_ "github.com/lib/pq"
)
func main() {
// Replace with your PostgreSQL connection details
connStr := "host=localhost dbname=mydatabase user=myuser password=mypassword sslmode=disable"
db, err := sql.Open("postgres", connStr)
if err != nil {
panic(err)
}
defer db.Close()
err = db.Ping()
if err != nil {
panic(err)
}
fmt.Println("Connected to PostgreSQL database")
}
Connected to PostgreSQL database
Performing Basic Operations
Here are examples of basic CRUD operations using Go with PostgreSQL:
Create (INSERT)
package main
import (
"database/sql"
"fmt"
_ "github.com/lib/pq"
)
func main() {
// Replace with your PostgreSQL connection details
connStr := "host=localhost dbname=mydatabase user=myuser password=mypassword sslmode=disable"
db, err := sql.Open("postgres", connStr)
if err != nil {
panic(err)
}
defer db.Close()
// Execute INSERT statement
_, err = db.Exec("INSERT INTO employees (name, age) VALUES ($1, $2)", "Alice", 30)
if err != nil {
panic(err)
}
fmt.Println("Record inserted successfully.")
}
Record inserted successfully.
Read (SELECT)
package main
import (
"database/sql"
"fmt"
_ "github.com/lib/pq"
)
func main() {
// Replace with your PostgreSQL connection details
connStr := "host=localhost dbname=mydatabase user=myuser password=mypassword sslmode=disable"
db, err := sql.Open("postgres", connStr)
if err != nil {
panic(err)
}
defer db.Close()
// Execute SELECT statement
rows, err := db.Query("SELECT name, age FROM employees WHERE age > $1", 25)
if err != nil {
panic(err)
}
defer rows.Close()
for rows.Next() {
var name string
var age int
err := rows.Scan(&name, &age)
if err != nil {
panic(err)
}
fmt.Printf("Name: %s, Age: %d\n", name, age)
}
}
Name: Alice, Age: 30
Update
package main
import (
"database/sql"
"fmt"
_ "github.com/lib/pq"
)
func main() {
// Replace with your PostgreSQL connection details
connStr := "host=localhost dbname=mydatabase user=myuser password=mypassword sslmode=disable"
db, err := sql.Open("postgres", connStr)
if err != nil {
panic(err)
}
defer db.Close()
// Execute UPDATE statement
_, err = db.Exec("UPDATE employees SET age = $1 WHERE name = $2", 31, "Alice")
if err != nil {
panic(err)
}
fmt.Println("Record updated successfully.")
}
Record updated successfully.
Delete
package main
import (
"database/sql"
"fmt"
_ "github.com/lib/pq"
)
func main() {
// Replace with your PostgreSQL connection details
connStr := "host=localhost dbname=mydatabase user=myuser password=mypassword sslmode=disable"
db, err := sql.Open("postgres", connStr)
if err != nil {
panic(err)
}
defer db.Close()
// Execute DELETE statement
_, err = db.Exec("DELETE FROM employees WHERE name = $1", "Alice")
if err != nil {
panic(err)
}
fmt.Println("Record deleted successfully.")
}
Record deleted successfully.
Conclusion
Explanation: This concludes the tutorial on using PostgreSQL with Go. You've learned how to install the necessary dependencies, connect to a PostgreSQL database, and perform basic CRUD operations.