adminDatabase Storage Engine and Data Files Checklist
A database stores data through a storage engine and files on disk. For MySQL and MariaDB, InnoDB is common for transactional workloads. Understanding where data lives helps with backup, recovery, disk planning and performance diagnosis.
Core principle
Database performance and reliability depend on memory, disk, logs, tablespace, indexes and write behavior. The database is not separate from the server filesystem.
Checklist
- Identify database engine and version.
- Check which storage engine tables use.
- Find the database data directory.
- Check disk usage of database files.
- Check whether binary logs are enabled.
- Check whether temporary files may grow.
- Check available disk and inode usage.
- Check backup size compared with database size.
- Monitor growth-heavy databases.
- Document storage layout and risk.
Reusable lesson
This applies to WordPress databases, analytics databases, automation logs, crawler data, queue tables and application event data.
When to Use This Checklist
Use this checklist when learning how MySQL or MariaDB stores data on disk and how that affects backup, recovery and server capacity.
Required Tools
SSH access, MySQL or MariaDB access, database admin user, df, du, database config, backup location
Before You Start
Do not delete database files manually from the filesystem. Use database-aware backup, cleanup and maintenance methods.
Structured Checklist Steps
- Check database version.
- Check table engines.
- Find data directory.
- Check database disk usage.
- Check binary logs.
- Check temp growth.
- Check disk and inode usage.
- Compare backup size.
- Monitor growth.
- Document storage risk.
Verification Steps
- Database data path is known.
- Storage engine is understood.
- Disk usage is safe.
- Growth-heavy data is identified.
- Backup size matches expectation.
Rollback Plan
If storage changes break database startup, restore the previous configuration and avoid moving database files without a tested maintenance plan.
Common Mistakes
- Deleting files inside /var/lib/mysql manually.
- Ignoring binary log growth.
- No disk growth monitoring.
- Not knowing database data directory.
- Confusing file backup with consistent database backup.
Related Commands
mysql -u root -p -e "SELECT VERSION();"
mysql -u root -p -e "SHOW TABLE STATUS FROM database_name;"
mysql -u root -p -e "SHOW VARIABLES LIKE 'datadir';"
sudo du -sh /var/lib/mysql
df -h
df -i