CREATE TABLE bit_columns (
 bit1_col BIT(1),
 bit8_col BIT(8),
 bit16_col BIT(16),
 bit64_col BIT(64)
);

package main
import (
	"database/sql"
	"fmt"
	"log"
	_ "github.com/go-sql-driver/mysql"
)
func main() {
	db, err := sql.Open("mysql", "user:pass@tcp(127.0.0.1:3306)/dbname")
	if err != nil {
		log.Fatal(err)
	}
	defer db.Close()
	rows, err := db.Query("SELECT * FROM bit_columns LIMIT 1")
	if err != nil {
		log.Fatal(err)
	}
	defer rows.Close()
	colTypes, err := rows.ColumnTypes()
	if err != nil {
		log.Fatal(err)
	}
	for _, colType := range colTypes {
		fmt.Println(colType.Name())
		fmt.Println(colType.DecimalSize())
		fmt.Println(colType.DatabaseTypeName())
		fmt.Println(colType.Length())
	}
}

bit1_col
0 0 false
BIT
0 false // <- why 0?
bit8_col
0 0 false
BIT
0 false // <- why 0?
bit16_col
0 0 false
BIT
0 false // <- why 0?
bit64_col
0 0 false
BIT
0 false // <- why 0?