> ISO-week: week that has more than 4 day and start in Sunday.
> In future I try implement 'IW' that is ISO-week, but now I work on different
> things.
> In current 7.0 is probably better for week operations use
> date_part('week', TIMESTAMP) than to_char().
Note that the above returns ISO-week, not some Sun-Sat thing ('dow' ==
"day of week" does that). I haven't yet implemented ISO-year (Karel?)
which would seem to be an essential piece to use ISO-week effectively.
- Thomas