MySQL vs PostgreSQL Backups: Key Differences Every Developer Should Know

Most developers treat mysqldump and pg_dump as interchangeable tools that do roughly the same thing. But underneath the surface, they behave very differently — and those differences directly affect whether your backups are safe, consistent, and actually usable when you need them.

How mysqldump Works

mysqldump is a logical backup tool. It connects to MySQL, reads data row by row, and writes SQL INSERT statements to stdout.

mysqldump -u root -p --single-transaction --routines --triggers mydb | gzip > backup.sql.gz

The critical flag is --single-transaction. Without it, mysqldump acquires a global read lock (FLUSH TABLES WITH READ LOCK) and holds it for the entire dump. On any table using MyISAM, this is unavoidable. With --single-transaction, MySQL opens a REPEATABLE READ transaction for InnoDB tables, giving you a consistent snapshot without locks. Writes continue uninterrupted.

How pg_dump Works

pg_dump also produces a logical backup, but it leans entirely on PostgreSQL’s MVCC (Multi-Version Concurrency Control) to guarantee consistency — no locking required.

pg_dump -U postgres -Fc mydb > backup.dump

When pg_dump starts, it takes a snapshot of the database at that point in time. Because PostgreSQL maintains multiple row versions, pg_dump sees a consistent view even as other transactions commit. No locks, no pauses, no interruption.

Locking Behavior: The Critical Difference

MySQL + InnoDB + --single-transaction: No write locks. Safe for production.

MySQL + MyISAM: Table-level locks required. Writes blocked during dump.

PostgreSQL: No write locks in any configuration. MVCC handles consistency.

Check for MyISAM tables with:

SELECT table_name, engine FROM information_schema.tables
WHERE table_schema = 'mydb' AND engine = 'MyISAM';

Backup Size and Compression

Both tools produce logical SQL output, which compresses well — typically 70-90% reduction. For MySQL, pipe through gzip or zstd. For PostgreSQL, the custom format (-Fc) uses zlib compression internally. The directory format (-Fd) supports parallel dumps for very large databases.

Point-in-Time Recovery

MySQL binary logs record every change as a stream of events. You can replay them on top of a base dump:

mysqlbinlog --stop-datetime="2026-03-21 14:30:00" binlog.000042 | mysql mydb

PostgreSQL WAL serves the same purpose, but the tooling is more integrated. PostgreSQL’s Point-in-Time Recovery (PITR) is generally more reliable and better integrated than MySQL’s binary log approach.

Common Pitfalls

MySQL Pitfalls

Missing --single-transaction: Without it, your dump locks the entire database

Character encoding mismatches: MySQL’s utf8 is only 3 bytes — use utf8mb4

Forgetting --routines and --triggers: Not included by default

Large tables causing timeouts: Long transactions can cause replication lag

PostgreSQL Pitfalls

Dumping as the wrong user: pg_dump only exports objects the connecting user can see

Roles not included: Use pg_dumpall --globals-only separately

Long-running transactions blocking VACUUM: Watch for table bloat during long dumps

Extension data: Verify extensions like timescaledb or postgis restore cleanly

How Calm Backup Handles Both Automatically

Calm Backup detects your database driver and applies the right defaults automatically.

For MySQL: --single-transaction, --routines, --triggers, correct charset handling. For PostgreSQL: custom format (-Fc) for compressed, parallel-restore-capable output.

Before upload, backups are encrypted locally using AES-256-GCM. Your encryption key never leaves your server. Running a backup:

php artisan backup:run # Laravel
vendor/bin/calmbackup run # Standalone

Restoring selects the correct tool (mysql vs pg_restore) automatically:

vendor/bin/calmbackup restore

The dashboard shows backup history, storage usage, and confirmation status. Each backup is verified with a checksum after upload. If a scheduled backup is missed, you receive an alert.