Question

My app keeps track of the state of about 1000 objects. Those objects are read from and written to a persistent store (serialized) in no particular order.

Right now the app uses the registry to store each object’s state. This is nice because:

• It is simple

• It is very fast

• Individual object’s state can be read/written without needing to read some larger entity (like pulling out a snippet from a large XML file)

• There is a decent editor (RegEdit) which allow easily manipulating individual items

Having said that, I’m wondering if there is a better way. SQLite seems like a possibility, but you don’t have the same level of multiple-reader/multiple-writer that you get with the registry, and no simple way to edit existing entries.

Any better suggestions? A bunch of flat files?

Answer 1

If you do begin to experiment with SQLite, you should know that ‘out of the box’ it might not seem as fast as you would like, but it can quickly be made to be much faster by applying some established optimization tips:

SQLite optimization

Depending on the size of the data and the amount of RAM available, one of the best performance gains will occur by setting sqlite to use an all-in-memory database rather than writing to disk.

For in-memory databases, pass NULL as the filename argument to sqlite3_open and make sure that TEMP_STORE is defined appropriately

On the other hand, if you tell sqlite to use the harddisk, then you will get a similar benefit to your current usage of RegEdit to manipulate the program’s data ‘on the fly.’

The way you could simulate your current RegEdit technique with sqlite would be to use the sqlite command-line tool to connect to the on-disk database. You can run UPDATE statements on the sql data from the command-line while your main program is running (and/or while it is paused in break mode).