# Waiting for 9.6 – Add log_line_prefix option ‘n’ for Unix epoch.

On 7th of September, Jeff Davis committed patch:

```Add log_line_prefix option 'n' for Unix epoch.

Prints time as Unix epoch with milliseconds.

Tomas Vondra, reviewed by Fabien Coelho.```

This could be useful, as it's simpler to calculate differences in epoch times than it is in timestamps.

So, let's see. Current, I have:

```\$ SHOW log_line_prefix ;
log_line_prefix
-----------------
%m %u@%d %p %r
(1 ROW)```

And this logs lines like:

`2015-09-22 19:29:19.286 CEST depesz@depesz 2925 [LOCAL] LOG:  duration: 0.058 ms  statement: SHOW log_line_prefix ;`

If I'd change %m into %n, and run the same query:

```\$ SHOW log_line_prefix ;
log_line_prefix
-----------------
%n %u@%d %p %r
(1 ROW)```

I'll get, much easier to work with in scripts:

`1442943024.558 depesz@depesz 2925 [LOCAL] LOG:  duration: 0.033 ms  statement: SHOW log_line_prefix ;`

Nice. I'm not actually big fan of epoch times, but I do realize that calculating difference between 1442943024.558 and 1442941298.516 is much easier than between ‘2015-09-22 17:30:24.558+00' and ‘2015-09-22 17:01:38.516+00'.

Thanks, guys.