If JET databases are part of Windows, how does one compact them?

Question

I'm certainly not aware of how many places Windows might use a JET database within the OS, but I am aware that when you have a JET database in MS-Access you have to run JET-Comp.exe on it every once in a while or the database will get too large and slow down and/or corrupt.

So where might one find a list of these JET databases within the Windows OS, and how might one Compact them?

Answer 1

To my knowledge, while Windows includes the JetSQL engine there are no JetSQL databases used by Windows itself. You can of course search the file system for mdb and accdb files.

If you want to compact a mdb or accdb file, you have the following options:

• The least pain is to install a program I wrote called PlaneDisaster.NET. Its provides an SQL interface to JetSQL and also has a compact and repair function
• If you know PowerShell, look at my script to create an MDB file you can adapt the SQLConfigDataSource call to use COMPACT_DB instead. If you have experience with PowerShell and PInvoke, its not that difficult. See this C# file.

As a final note, if you want to compact an Access database from a 64 bit process, or compact an accdb file, you need the office 2010 driver.