From UnixNano() to Time{}

Question

I want to convert a UnixNano() int64 time stamp back to a time.Time{}.

Taking a step back, here is the larger issue.

We have a database with timestamps, we use these timestamps to pull entries. In nanotime there should never be duplicate timestamps. The database is an embedded SQLite3 database (via the "github.com/mattn/go-sqlite3" driver) with the stamp held in an INTEGER column. We do some sorting and filtering with the number value, in the form of clauses on selects and within a few views.

Thus when we bind our integers to our prepared statements like:

INSERT INTO "event" ("timestamp", "command", "data") VALUES (?, ?, ?)

we bind time.Now().UnixNano().

However when I try to convert the item to a data structure, I find I cannot accurately take a UnixNano time and reconstitute it back to a time.Time{} structure.

They never match.

How should I do this?

Answer 1

t1 := time.Now()
fmt.Println(t1, t1.UnixNano())
t2 := time.Unix(0, t1.UnixNano())
fmt.Println(t2, t2.UnixNano())

gives you

2009-11-10 23:00:00 +0000 UTC 1257894000000000000
2009-11-10 23:00:00 +0000 UTC 1257894000000000000

http://play.golang.org/p/Q68IaR9zPK

BTW, are you sure that the integer value saved to the database is not truncated (e.g. can store int64)?