Resource Files

[Jean Christophe Avard]

Hi! I am designing a database driven application. The main purpose of this
application is to print signs and label with plant (botanical) information
and a picture of the plant. This is mainly intended for the nurseries. Our
application comes with 3500+ full plants description and hi-res picture for
each one, while the end user can add his own into the db. However, my boss
don't want the end user to have directly access to the picture (the one
provided with the application). At first, I thought I was going to store
only the path in a table field, but now I have to store the image into a
database. Since the picture are hi resolution, the picture will be al least
1.5+ mb, so we'll need two database (even more), that will for sure slow
down the cpu performance. So on another forum, some people told me to look
out for Resource File. I googled to find some information, few so far. What
I'd like to know from you guys, is what would be the way to go? Storing
picture in multiple database? Using Resource file??? Or anyone has some
better trick? Thank you! Your help is really appreciated!

Jean Christophe Avard

 

[Chris]

Hi! I am designing a database driven application. The main purpose of this
application is to print signs and label with plant (botanical) information
and a picture of the plant. This is mainly intended for the nurseries. Our
application comes with 3500+ full plants description and hi-res picture for
each one, while the end user can add his own into the db. However, my boss
don't want the end user to have directly access to the picture (the one
provided with the application). At first, I thought I was going to store
only the path in a table field, but now I have to store the image into a
database. Since the picture are hi resolution, the picture will be al least
1.5+ mb, so we'll need two database (even more), that will for sure slow
down the cpu performance. So on another forum, some people told me to look
out for Resource File. I googled to find some information, few so far. What
I'd like to know from you guys, is what would be the way to go? Storing
picture in multiple database? Using Resource file??? Or anyone has some
better trick? Thank you! Your help is really appreciated!

Jean Christophe Avard

Why not just encrypt the picture file? This way you can save them to
the hard drive, but a normal file can't open it. As you load the file
into memory you can decrypt it and load it into a image object using a
memory stream.

Just an idea.
Chris

 

[lgbjr]

Hello,

chris actually beat me to it, but I would also suggest encrypting the files
(jpeg or bmp) rather than storing them in the DB. whether it's Jet or SQL,
about the maximum size of a DB is 2GB, and with 3500+ 1.5MB pics to start,
you'd need at least 3 seperate DBs.

Check the following site for some quick pic encryption info:

http://www.efg2.com/Lab/ImageProcessing/CryptImage.htm

Encrypt your images. If the user adds images, have them stored in a
sub-directory of your images directory. When your loading images to view or
print, if they come from the user's sub-directory, skip the decryption
process.

HTH
Lee

 

[Guest]

Saw your reply regarding the size of the Database. I wasn't aware that
either Acess or SQL databases had a limit on size. Does this apply to the
recent versions of both?

 

[lgbjr]

hi Dennis,

For Access, the max size of an MDB file is 2GB. You can however use multiple
MDB files with tables linked to one master MDB file, so you could
effectively have a database that is only limited by disk space. However,
from experience using Acess, you'd be pulling your hair out long before you
reached the initial 2GB limit on a single MDB file (just waiting for
transactions to process)

For MySQL, I apologize. I should have been more specific. the limitation on
size is not really related to MySQL (though it was in the past). The current
maximum table size in MySQL is 65536 TB (that's HUGE). The limitation is
based on the OS / file system type. A quick guide:

Operating System File-size Limit
Linux 2.2-Intel 32-bit 2GB (LFS: 4GB)
Linux 2.4+ (using ext3 filesystem) 4TB
Solaris 9/10 16TB
NetWare w/NSS filesystem 8TB
win32 w/ FAT/FAT32 2GB/4GB
win32 w/ NTFS 2TB (possibly larger)
MacOS X w/ HFS+ 2TB


I typically don't make the assumption that people are using NTFS, so I
typically say 2GB for MySQL as well, just to be safe, though I guess most
people are using at least FAT32 now, so 4GB would be ok.

Cheers
Lee