Locking processes vary depending on the application and the database management system used to store the data. Locks are critical for file and process management. Understanding how locks work can help you manage your workflows better and potentially alleviate frustrations.
A mobile geodatabase is a single-user geodatabase stored in an SQLite database. When a project containing a mobile geodatabase is opened, ArcGIS AllSource and SQLite both apply locks on the underlying data to ensure data integrity (in the folder containing the mobile geodatabase, this is indicated as .geodatabase-conch). This means that only one user at a time can modify data in a mobile geodatabase. When ArcGIS AllSource or the project associated with the mobile geodatabase is closed, the lock file is automatically deleted, making it available for another to use.
While SQLite is a self-contained database file format that stores the entire database in a single file on disk, SQLite creates and uses various temporary files while processing a database. When working with a mobile geodatabase, some of these temporary files may include the following:
- .geodatabase-wal—write-ahead log
- .geodatabase-shm—shared memory file
- .geodatabase-journal—rollback journal
If a process ends prematurely, some of these temporary files, including the lock file, may be left in the folder. If you cannot edit a mobile geodatabase or delete it, one of the following may be responsible:
- The data is being accessed by two or more applications simultaneously. Close one of the applications so you can perform your operation.
- Another process on your computer is still accessing the data because it did not terminate properly. For example, even though an application does not appear to be running, it may not have closed properly and the data may still be locked. Check the Task Manager for such detached processes and end them.
For more information on these and other temporary SQLite files, see Temporary files used by SQLite.