How to handle errors and exceptions when executing SQL queries in Go?

In Go, you can handle errors and exceptions when executing SQL queries by utilizing the database/sql package's error handling features. Here's a step-by-step guide on how to handle them effectively:

Import the necessary packages:

import (
    "database/sql"
    "fmt"
    "log"
)

Establish a database connection:

dsn := "<your-database-connection-string>"
db, err := sql.Open("driver-name", dsn)
if err != nil {
    log.Fatal(err)
}
defer db.Close()

Note: Replace driver-name with the appropriate SQL driver package, such as "postgres" for PostgreSQL or "mysql" for MySQL.

Execute the SQL query:

query := "SELECT * FROM table_name"
rows, err := db.Query(query)
if err != nil {
    log.Fatal(err)
}
defer rows.Close()

Iterate over the rows to fetch the data:

for rows.Next() {
    var column1 string
    var column2 int
    // Declare other variables for columns as needed
    
    err = rows.Scan(&column1, &column2)
    if err != nil {
        log.Fatal(err)
    }
    
    // Process the fetched data
    fmt.Println(column1, column2)
}

if rows.Err() != nil {
    log.Fatal(rows.Err())
}

Handle errors and exceptions during database operations: Whenever you encounter an error or exception, you can choose how to handle it based on your application's requirements. Some common approaches include logging the error, retrying the query, or returning an error message to the user.

Additionally, the error instance returned by sql.Open, db.Query, rows.Next, rows.Scan, and rows.Err provides more information about the specific error occurred. Therefore, you can customize your error handling based on the specific error type or message received.

By following these steps, you can effectively handle errors and exceptions when executing SQL queries in Go and ensure smooth database operations.