Question

I am trying to convert decimal value to date in select statement

SELECT user_id, extend(dbinfo("UTC_TO_DATETIME",min(creationdate)), year to fraction) AS earned_date
FROM message

But I am getting this error

 Value exceeds limit of INTEGER precision

The field definition in table is this

  creationDate      decimal(14,0) NOT NULL

It seems I am not using the right way to do the conversion, any idea?

Answer 1

I don’t think you need to use EXTEND in this context – EXTEND is used to change the scale of DATETIME and INTERVAL values.

UTC_TO_DATETIME returns a DATETIME value already.

Have you tried:

SELECT user_id, dbinfo("UTC_TO_DATETIME",min(creationdate)) AS earned_date
  FROM message

What does that produce?

UPDATE

Ahh, an example makes all the difference!

The value you are passing is not a UTC datetime as UTC_TO_DATETIME expects. The function expects an integer representing seconds, not milliseconds. It’s as simple as that.

DBINFO('UTC_TO_DATETIME', 1329994172574) exceeds integer precision.

DBINFO('UTC_TO_DATETIME', 1329994172574/1000) on the other hand, produces:

2012-02-23 21:49:32, which I guess is what you expect?

If you have a look at the link I provided earlier, it explains treatment of fractional seconds. (Spoiler: they’re ignored.)

If the fractional seconds are critically important, I guess you’re going to have to EXTEND the results of this function to fractional seconds, and then add MOD(creationdate,1000)/1000 to it.

For example:

SELECT user_id, 
      (dbinfo("UTC_TO_DATETIME", MIN(creationdate)/1000 )::DATETIME YEAR TO FRACTION(3)
        + (MOD(MIN(creationdate),1000)/1000) UNITS FRACTION) AS earned_date
  FROM message

(But personally, I would be inclined to put this logic into an SPL anyway, so you could call it like:
SELECT user_id, millis_to_time(MIN(creationdate))... and avoid writing this sort of complex algorithm all over the place.)