How was the insertion of a new column into a database table carried out?

Adding a new column to a database table is usually done using the SQL command ALTER TABLE. In Go (Golang), you can use the database/sql package to execute the corresponding SQL query.

Example of adding a new_column of type VARCHAR(255) to the users table:

import (
    "database/sql"
    _ "github.com/lib/pq" // example for PostgreSQL
    "log"
)

func addColumn(db *sql.DB) error {
    query := `ALTER TABLE users ADD COLUMN new_column VARCHAR(255);`
    _, err := db.Exec(query)
    return err
}

func main() {
    db, err := sql.Open("postgres", "user=postgres dbname=mydb sslmode=disable")
    if err != nil {
        log.Fatal(err)
    }
    defer db.Close()

    if err := addColumn(db); err != nil {
        log.Fatalf("Error adding column: %v", err)
    }
    log.Println("Column successfully added")
}

Thus, adding a column involves executing an SQL command through Go code.