In addition to the database file, UltraLite creates and maintains a temporary file during database operation. You do not need to work with or maintain the file in any way.
Temporary files are only used by UltraLite and are maintained in the same file path (if one exists) as the UltraLite database itself. The temporary file has the same file name as the database you have created, but with the following difference:
For file-based platforms The tilde is included in the extension of the file (that is, .~db). For example, if you run the CustDB.udb sample database, the temporary file called CustDB.~db is maintained in the same directory as this file.
For record-based platforms The tilde is appended to the end of the name of the file. For example, if CustDB.udb existed as a record-based file for Palm OS, the temporary file for it would be maintained as CustDB.udb~.
You can safely delete the temporary file without loss of data—as long as UltraLite is not running. It does not contain information that may be required across sessions.
UltraLite temporary tables