mysql建表失败 about gorm HOT 1 CLOSED

package main

import (
    "database/sql"
    "fmt"
    _ "github.com/go-sql-driver/mysql"
    "github.com/jinzhu/gorm"
    "time"
)

type Address struct {
    Id        int
    CreatedAt time.Time
    UpdatedAt time.Time
    DeletedAt time.Time
    Address1  string         `sql:"not null;unique"`
    Address2  string         `sql:"type:varchar(100);unique"`
    Post      sql.NullString `sql:not null`
}

func main() {
    db, err := gorm.Open("mysql", "gorm:gorm@/gorm?charset=utf8&parseTime=True")
    if err != nil {
        panic(err)
    }

    db.Exec("drop table addresses")
    if err = db.CreateTable(Address{}).Error; err != nil {
        panic(fmt.Sprintf("No error should happen when create table, but got %+v", err))
    }
}