Hello

Dont want to spam with too many posts so just posting my 2 questions as an one topic.

1) what is the best way to file paths? For example..
"C:/Users/Admin/...../..../...

Don't know what is the maximum size i should give to my data-type. The database i'm using doesn't have a TEXT datatype like MYSQL does so i probably need to use a VARCHAR with a size.

2) When comparing CHAR against VARCHAR with '=' sometimes it doesn't work, it says i need a cast.. But when i use the 'LIKE' operator - it works.. Why is that?

Well that should be the max. size of a path in whatever operating system you want the path to be valid. In Windows there is a limit that can probably be found out by searching the Microsoft website. For any *nix system this depends on the file system used.

The CHAR datatype stores values padded with blanks so a CHAR(10) is always 10 characters long. If you store 'HELLO' into such a column, the DBMS will add 5 spaces to the end of the value.
Those spaces will be taken into account when comparing values ('HELLO' is different from 'HELLO ')

My recommendation: don't use CHAR unless you really know that the length of your data is fixed

and why is that a secret?

1) That's a good way to store paths. The length of a path is limited by either the Operating System, the File System, or the Device Driver. The limits that I've seen are 32 characters to 1023 characters. Most modern systems store filenames using a large character set (such as Unicode, UTF-8, etc) and most archaic systems use single byte characters.

Pick a length that suits you, almost any value will cause problems somewhere!

3) As Shammat pointed out, CHAR() columns space fill on the right. CHAR() comparisons are tricky for many reasons, I would avoid them until you have the time to learn in detail how they work.

-PatP

No not a secret at all.

I was at that point using Apache-Derby but now i have switched to SQLite.

thanks for answers