September 2007 - Posts
Q: Is there a good whitepaper/documentation that describes the SSCE components?
A: Yes there is a knowledge base article, http://support.microsoft.com/?kbid=920700, lists the major changes (since v3.0), all relevant downloads, performance gains in the new runtime and a list of known issues with v3.1 (mostly related to working under Vista).
Q: When I go to upgrade my database there are a number of Encryption options. What do they all mean?
A: To support older operating systems, with older encryption algorithms, and newer, more secure encryption, SQL Server Compact 3.5 supports backward-compatible encryption modes. The encryption modes available in the Upgrade to SQL Server Compact 3.5 Database dialog box are as described in the following list.
-
Platform Default: When you create or upgrade SQL Server Compact databases, Encryption mode will select the default encryption for the operating system. By creating a database on one of the newer platforms shown here, older platforms (such as Windows CE 4.2 or Windows Mobile 2003) will be unable to open encrypted SQL Server Compact files.
-
Engine Default: By default, the encryption mode for the SQL Server Compact 3.5 database file will not work on Windows CE 4.2 or Windows Mobile 2003 Software for Pocket PC. This encryption mode will work on all newer SQL Server Compact 3.5 supported platforms.
-
PPC2003 Compatibility: While less secure, this option can be used to support older and newer operating systems
[Sources from Ambrish's post on the SQL Server CE 3.5 forum]
Q: I've attempted to open a v3.1 SSCE database file using the SSCE 3.5 runtime (still in beta) and it is failing?
A: Despite using the same extension (ie .sdf) not only are SSCE 3.5 db file not backward compatible with older runtimes, SSCE 3.1 and earlier db files are not compatible with the new runtime. If you are building an application using the new SSCE 3.5 runtime you need to make sure you call the upgrade api on the SqlCeEngine class. Alternatively you can use Visual Studio 2008 to connect to an old database file, which will prompt you to upgrade.
Q: What does the following error message mean?
The lock manager has run out of space for additional locks. This can be caused by large transactions, by large sort operations, or by operations where SQL Server Compact Edition creates temporary tables. You cannot increase the lock space
A: As the error message implies it is caused by large transations but the question is how large? According to the product team the limit on the number of lock references in v3.0/v3.1 was 2^18-1 which equates to 1Gb of pages. In v3.5 this has been increased to 2^32-1 or 17.6Tb of pages!
More Posts