Why MySQL

What does this bring for users?

• Much better performance compared to MSSQL-CE
• No size limit for your MediaLibrary

How big is the impact of chosen database?

Test with 4 shares:

• local folder with BluRay images (type "Movie")
• local folder with custom videos (type "Video")
• folder with Series on NAS (type "Series")
• folder with Music on NAS (type "Audio")

A normal import using the default SQL-CE database took ~9 minutes. This includes thumbnail extraction and DB access.
Using MySQL on same PC the import time decreased to ~4 minutes! It's twice as fast as MSSQL-CE.

The reason for this is probably the fact, that MSSQL-CE is run in the process of the host (MP2-Server) and it's not as efficient as a dedicated database process. On analysis I found out, that most time was spent on a "DELETE" SQL-statement that uses subqueries with "LIKE" on the path part. MySQL performs a lot better, probably because it is able to use the existing index on path.
To get a number: for MSSQL-CE the time for DB-Access was double of the time required for thumbnail creation! (160 sec vs. 80 sec!)