On 7/19/06, Cesar David Rodas Maldonado <[EMAIL PROTECTED]> wrote:
Do you know for how much money?
On 7/19/06, Jay Sprenkle <[EMAIL PROTECTED]> wrote:
>
> The author of Sqlite also sells a version that compresses and encrypts
> the database.
from this page: http://www.hwaci.com/sw/sqlite/prosupport.html
3.0 Encrypted Databases
An enhanced version of SQLite is available (for both versions 2.8 and
3.3) that encrypts its database files to help prevent unauthorized
access or modification. The entire database file is encrypted2. To an
outside observer, the database file appears to contain white noise.
There is nothing2 that identifies the file as an SQLite database.
The enhanced SQLite with encryption support can continue to read and
write ordinary unencrypted databases without any performance penalty.
You can use the ATTACH SQL command to attach an encrypted database to
an unencrypted database or to attach an unencrypted database to an
encrypted one. The password to a database can be changed at any time,
though doing so is an expensive operation roughly comparable to
VACUUM.
The encryption extension descrypts each page of data as it is read
from the disk and reencrypts it as modified versions are written back
to the disk. But the primary database file and the rollback journal
are encrypted. A very fast encryption algorithm is used, but even so
it takes time to do all of that encryption and decryption. So when
encryption is enabled, there is about a 50% performance loss.
The encrypted database enhancements for SQLite are available in
source-code form for a one-time licensing fee of $2000 (US). A
technical support contract is also recommended but is not required.
There are no per-copy royalties. The one-time fee entitles the
licensee to free copies of all future updates to the code. You can
purchase a perpetual license to the SQLite Encryption Extension online
or call +1.704.948.4565 or write to [EMAIL PROTECTED] for
additional information.
4.0 Compressed and Encrypted Read-Only Databases
A separate extension is available that allows SQLite to read database
files that have been both compressed and encrypted. The amount of
compression depends on the kind of data that is stored, of course, but
typically is in the 50% to 70% range.
Compressed databases are read-only. To create a compressed database,
first construct a normal uncompressed database holding the desired
data. Then run a special command-line tool (included with the
extension) that converts the uncompressed database into a much smaller
compressed and encrypted database. Afterwards the compressed database
can be read (but not written) using this extension.
Compressed databases are useful in products that contain a large fixed
data set that needs to be squeezed into the limited memory space of a
PDA or other gadget or onto a single CD-ROM or DVD. If an application
has both a large fixed data set but also some smaller read/write
tables, then the large fixed data set can be stored in a compressed
database file and the variable database can be held in a separate
uncompressed read/write database. The two databases can be accessed as
if they were one using the ATTACH command in SQLite.
The compressed database extension is separate from the encrypted
database extension described in section 3.0 above. But the two
extensions can be used together if desired. The compressed database
extension is currently in development. A finished version is expected
to be available with the release of SQLite version 3.3.0 in January of
2006. However, beta copies are available immediately for preliminary
testing purposes.
The compressed database extension for SQLite are available in
source-code form for a one-time licensing fee of $2000 (US). A
technical support contract is also recommended but is not required.
There are no per-copy royalties. The one-time fee entitles the
licensee to free copies of all future updates to the code. Call
704.948.4565 or write to [EMAIL PROTECTED] for additional
information.
5.0 Custom Modifications
Some projects can be best served by a customized version of SQLite
with specialized capabilities and/or extensions. For example:
* Specialize performance tuning or optimization for a particular
class of query
* Ports of SQLite to new operating systems or execution environments
* Application-specific extensions to the SQL query language
* Enhanced security features
* Bindings to alternative programming languages
You should not have to settle for a proprietary database library that
lacks needed features when you can have full source code and unlimited
rights to a database that meets your needs exactly and completely.
Just let us know what your special requirements are. We can reply with
either a fixed-priced bid or give you an estimate and an hourly
billing rate.
