I think we'd have to know more about both your environment and the MySQL server's to answer the "Why?". POSIX::strftime honors locale, so the value of $date depends on your LC_foo environment variables. MySQL may be compiled to store utf-8 or some other character encoding.

Question a): I think you should store datetime fields the way MySQL wants, as a datetime column type. Storing them as strings denies you the very useful builtin date & time functions of MySQL. You can retrieve datetimes with MySQL's DATE_FORMAT() function to get most any representation you want. If you have serious encoding problems, you can fall back on unix epoch time for retrieval and then apply localtime.

Question b): Some browsers pretty much ignore http headers. Try specifying the character encoding in the html tag, as well.

DATE_FORMAT(date,format)

Formats the date value according to the format string.

The following specifiers may be used in the format string. The ‘%’ character is required before format specifier characters.

Ranges for the month and day specifiers begin with zero due to the fact that MySQL allows the storing of incomplete dates such as '2004-00-00'.

mysql> SELECT DATE_FORMAT('1997-10-04 22:23:00', '%W %M %Y');
        -> 'Saturday October 1997'
mysql> SELECT DATE_FORMAT('1997-10-04 22:23:00', '%H:%i:%s');
        -> '22:23:00'
mysql> SELECT DATE_FORMAT('1997-10-04 22:23:00',

                          '%D %y %a %d %m %b %j');
        -> '4th 97 Sat 04 10 Oct 277'
mysql> SELECT DATE_FORMAT('1997-10-04 22:23:00',
                          '%H %k %I %r %T %S %w');
        -> '22 22 10 10:23:00 PM 22:23:00 00 6'
mysql> SELECT DATE_FORMAT('1999-01-01', '%X %V');
        -> '1998 52'
mysql> SELECT DATE_FORMAT('2006-06-00', '%d');

        -> '00'

This allows you to format your DATETIME or TIMESTAMP fields, but it doesn't seem to honor your locale setting. As a matter of fact, MySQL does not seem to know how to set the locale at all. It can however set on a per table basis the character set to use (latin1, UTF8, ...).

If you really want to have your DATETIME fields in Greek, have a look at DBIx::Class and its inflate/deflate mechanism or the ColumnHandlers method from DBIx::DataModel which can transform your fields in pretty any way you like.

And why do i need to use encode to switch from greek => utf8?

I'm not the big expert on encoding, but I think the whole encoding thing must be perfectly aligned for it to work. It is best to have the same encoding set on both the input machine/layer, the storage layer ( i.e. the database) and the output machine/layer. If somewhere in this chain of things there is a different encoding then you get "funny" characters. So if you start with "greek" encoding, you better have this all the way through to avoid problems.

Other monks much more versed in the ways of Unicode and the like probably can tell you more about it or you can have a look at perluniintro and perlunicode.

CountZero

"If you have four groups working on a compiler, you'll get a 4-pass compiler." - Conway's Law

INSERT INTO mytable (mydatetimefield) values (NOW());
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sub now {
    my @time = localtime;
    return sprintf '%d-%02d-%02d %02d:%02d:%02d',
            $time[5]+1900, $time[4]+1, $time[3], $time[2], $time[1], $
+time[0];
          #     year          month     day       hour      min       
+sec
}
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