使用GORM和Postgresql时如何在Go中节省数据库时间?

I'm currently parsing a time string and saving it to the db (Postgresql):

event.Time, _ := time.Parse("3:04 PM", "9:00 PM")
// value of event.Time now is: 0000-01-01 21:00:00 +0000 UTC
db.Create(&event)

It's giving me this error: pq: R:"DateTimeParseError" S:"ERROR" C:"22008" M:"date/time field value out of range: \"0000-01-01T21:00:00Z\"" F:"datetime.c" L:"3540"

event.Time⁠⁠⁠⁠'s type is time.Time.

I also tried setting event.Time's type to string and using time data type in postgresql:

type Event struct {
  Time string `gorm:"type:time
}

But now I'm getting an error when fetching records in the db:

sql: Scan error on column index 4: unsupported driver -> Scan pair: time.Time -> *string

Investigated this issue further. Currently, there's no support in GORM for any Date/Time types except timestamp with time zone

See this part of code from dialect_postgres.go:

case reflect.Struct:
   if _, ok := dataValue.Interface().(time.Time); ok {
      sqlType = "timestamp with time zone"
}

So basically I see two options for you:

Either use varchar(10) in DB, and string in Go, an simply save it as "9:00 PM" (where 10 is some number that suits you)

Or use timestamp with time zone in DB, time.Time in Go, and format your date part as a constant date, 01/01/1970, for example:

time.Parse("2006-01-02 3:04PM", "1970-01-01 9:00PM")

In that case you'll have to omit the date part in your presentation, but if you plan to select by date range, that could work better for you.

When updating the DATETIME field in SQL, the Go string must be in this format: time.Now().Format(time.RFC3339).

From Postgres perspective the error stems from there being no year 0000. If you don't the date you may just be able to add 1 year to the converted timestamp giving '0001-01-01T21:00:00+00' which is a valid Postgres timestamp.

select '0000-01-01T21:00:00+00'::timestamptz at time zone 'UTC' 
ERROR:  date/time field value out of range: "0000-01-01T21:00:00+00"

Gives he same error. And just as a demonstration 1 day before 0001-01-01 gives:

select '0001-01-01T21:00:00+00'::timestamptz at time zone 'UTC' - interval '1 day' "day_before_1/1/1";
--day_before_1/1/1
--0001-12-31 21:00:00 BC