Golang proposal: database/sql: Can add DriverName() string into sql.DB and sql.Tx

Proposal Details

We often need to adapt to different databases (e.g., PostgreSQL, MySQL), so we need to distinguish them using driverName. Since sql.DB or sql.Tx objects don't provide a DriverName() method, we have to pass the driverName parameter ourselves, as shown below:

func createGooseTable(db *sql.DB, driverName, gooseTable string) error {
    var createSQL string
    switch driverName {
    case "mysql":
        createSQL = fmt.Sprintf(`CREATE TABLE IF NOT EXISTS %s (
            id BIGINT AUTO_INCREMENT PRIMARY KEY,
            version_id BIGINT NOT NULL,
            is_applied TINYINT DEFAULT 1 NOT NULL, -- 默认标记为已应用
            tstamp TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
            description VARCHAR(255)
        )`, gooseTable)
    case "postgres":
        createSQL = fmt.Sprintf(`CREATE TABLE IF NOT EXISTS %s (
            id SERIAL PRIMARY KEY,
            version_id BIGINT NOT NULL,
            is_applied BOOLEAN DEFAULT TRUE NOT NULL,
            tstamp TIMESTAMPTZ DEFAULT NOW(),
            description TEXT
        )`, gooseTable)
    default:
        return fmt.Errorf("unsupported database type: %s", driver)
    }
    _, err := db.Exec(createSQL)
    return err
}

Many such functions require this extra driverName parameter. If sql.DB and sql.Tx could provide this method, it would be much more convenient and save one parameter. This would also be a very small change.