SQLite Database files are more vulnerable to corruption issues because they have a complicated file structure.Any small error or issue can easily corrupt the entire database. Although the SQLite database is resistant to corruption, you shouldn’t be careless.

SQLite is the most preferred choice for businesses for
local/client storage in application software. It is also considered one of the most deployed database
applications used by different operating systems, browsers, and smartphones.

Due to complex queries and functions, SQLite databases are prone to corruption errors. Thus, you
should take the essential steps to protect your SQLite databases. In this article, we will discuss the most
common SQLite database issues and their solutions.

Common Errors of SQLite Database

When the SQLite database becomes inaccessible, you’ll find any of the following errors.

"SQLite3: OperationError: unable to open database file."
"SQLSTATE: General Error: 14 unable to open database file."

Why Does SQLite Database Get Corrupt?

There is no specific reason behind the corruption of SQLite databases. However, the SQLite database
can get damaged due to the following reasons:

File Overwriting Problem

File overwriting is one of the most common problems that cause SQLite database corruption. It
usually happens when a user continuously opens and closes a file descriptor; this can cause
overwrite issues in the databases. Also, SQLite uses auxiliary journal files to fix the databases, and if
the user deletes or moves the journal files from their original location, it can cause overwriting issues.

Moreover, if any backup process is running in the background, it will create a backup of the SQLite
database even if the transaction is in active mode. The backup usually contains the logs of the
previous state and earlier transactions, which display the corruption error at the end.

File Locking Issues

SQLite allows you to lock the files of the database, but this can cause trouble if you work with two
different processes, such as:

• Using the file system for locking the SQLite database when there are unfixed bugs can cause
  errors

• It is necessary to use POSIX Advisory Lock for default locking while running SQLite database for
  Unix users

• SQLite database gets corrupt if the system call, close(), interrupts the locking action of SQLite
  database

• If you use different protocols at the same time in SQLite databases, such as SQLite3_Open_v2()
  and SQLite3_vfs, the SQLite database gets corrupt

• If one application uses the POSIX advisory locks and another app is using dot-file locking, the two
  applications can’t see each other’s locks, which can corrupt the SQLite database

Apart from that, attaching multiple files in the same network can cause issues in the SQLite
database.

Storage Files Issues

Any interruption in the hard disk or flash memory while using the SQLite database will result in errors.
Thus, it is mandatory to have sufficient disk space for the proper functioning of the SQLite database.
Also, if the storage media is full, you shouldn’t write anything to it because it can lead to errors.

Data Synchronization Errors

Often, the sync command of SQLite Server can result in failure and cause rollback actions further.
This is termed ACID property violation, which often causes errors in SQLite databases.

How to fix SQLite Database Corruption Errors?

SQLite database corruption can lead to permanent loss of data files. And if it happens, you won’t be able
to open the corrupt SQLite database. In such circumstances, you must repair the SQLite database and
take a complete backup.

You can repair the SQLite database using the manual method as well as an alternative tool. Let’s take a
look at the steps of the manual process to repair SQLite databases.

• Locate and launch the Database browser for SQLite on your computer and click the Execute tab
  of SQL to start the database check-in command.

• Type PRAGMA integrity checks in the command prompt, and click the Play button.

• If the database file is corrupt, you will receive an error message.

• Click the File button on the taskbar, select the Export option and click SQL file.

• Now, click the Export SQL dialogue box and select the objects that you want to export.

• Here, you can import the database file, select the Import options, and click Database from the
  SQL file.

Performing these steps can resolve minor corruption in the SQLite databases. However, if the
corruption error has severely damaged the databases, you need an alternative solution to repair the
databases. There are plenty of tools to restore corrupt SQLite databases, but not every tool is ideal
for improving corrupt/damaged SQLite databases.

Kernel SQLite Database Recovery is an excellent tool that allows you to retrieve the SQLite
database’s damaged, corrupt, and deleted contents. Using this utility, you can quickly restore corrupt
db, db3, sqlite, sqlite2, and sqlite3 files. You can recover all the objects, including tables and other
properties like indexes, triggers, and other items.

The tool is designed with intelligent algorithms and technologies the enable you to recover data in the
same format without affecting the original hierarchy. Before retrieving the data, you can also have a
preview of the data.

Key Takeaways

SQLite database corruption can result in permanent loss of data tables and properties. Thus, it will
help if you take preventive measures to protect your data against significant corruption errors. This
article talked about the most common SQLite database errors and solutions that you can use to
repair corrupt/damaged SQLite databases.

While you’re at it, have a look at this nice tutorial which shows the differences between Logical SQL queries and Physical SQL queries.