How to Resolve “Skipping the Data of Table mysql.event” Warning in MySQL Dump


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When working with mysqldump on newer MySQL versions (particularly after Debian upgrades), you'll often encounter this warning:

-- Warning: Skipping the data of table mysql.event. Specify the --events option explicitly.

This occurs because MySQL's Event Scheduler stores its data in a special system table (mysql.event) that requires explicit handling during backup operations.

MySQL intentionally separates event definitions from regular table dumps for several reasons:

  • Event permissions are handled differently than table data
  • Events might contain sensitive schedule information
  • The Event Scheduler might be disabled on the target server

Here are your main approaches to handle this:

Option 1: Include Events Properly

To fully backup your events along with other database content:

mysqldump --events --all-databases > full_backup.sql

Or for specific databases:

mysqldump --events db_name > db_backup.sql

Option 2: Suppress the Warning (If You Don't Need Events)

If you're certain you don't need to backup events:

mysqldump --skip-events --all-databases 2> /dev/null

Or more cleanly by redirecting stderr:

mysqldump --skip-events --all-databases 2>&1 | grep -v "Warning: Skipping the data"

Option 3: Permanent Configuration

Add this to your ~/.my.cnf to make it default behavior:

[mysqldump]
events

After creating your dump file, you can verify events were included:

grep "CREATE EVENT" your_dump_file.sql

Or check what was excluded:

grep "Warning:" mysqldump.log

For production environments with many events, consider this comprehensive backup script:

#!/bin/bash
DATE=$(date +%Y%m%d)
MYSQL_USER="backup_user"
MYSQL_PASS="secure_password"

# Backup with events and routines
mysqldump --user=$MYSQL_USER --password=$MYSQL_PASS \
--events --routines --triggers --single-transaction \
--all-databases > full_backup_$DATE.sql 2> backup_errors.log

# Compress and remove old backups
gzip full_backup_$DATE.sql
find /backups -name "*.gz" -mtime +30 -delete

If you've recently upgraded your MySQL environment or switched to a new server, you might encounter this warning during backups:

-- Warning: Skipping the data of table mysql.event. Specify the --events option explicitly.

This occurs because MySQL events (scheduled tasks) are stored in a special system table that requires explicit handling during dump operations.

The mysql.event table contains scheduled event definitions for the MySQL Event Scheduler. Due to security considerations and the special nature of event objects, MySQL requires explicit flags to include them in dumps.

Option 1: Include Events in Your Backup

If you actually use MySQL events and want to preserve them:

mysqldump --events --all-databases > full_backup.sql

Or for specific databases:

mysqldump --events -u username -p database_name > backup.sql

Option 2: Suppress the Warning (When You Don't Need Events)

To completely eliminate the warning without including events:

mysqldump --skip-events --all-databases 2> /dev/null > backup.sql

For Windows:

mysqldump --skip-events --all-databases 2> nul > backup.sql

Here's how to create a robust backup script that properly handles events:

#!/bin/bash
# MySQL credentials
USER="backup_user"
PASS="secure_password"
HOST="localhost"

# Backup directory
BACKUP_DIR="/var/backups/mysql"

# Get all databases
DATABASES=$(mysql -u$USER -p$PASS -h$HOST -e "SHOW DATABASES;" | grep -Ev "(Database|information_schema|performance_schema)")

# Backup each database
for DB in $DATABASES; do
  echo "Backing up $DB"
  mysqldump --events --single-transaction -u$USER -p$PASS -h$HOST $DB > $BACKUP_DIR/$DB-$(date +%Y%m%d).sql
done

# Optional: Backup events separately for more control
mysqldump --events --skip-triggers --no-create-db --no-create-info --no-data mysql > $BACKUP_DIR/mysql_events-$(date +%Y%m%d).sql

To see if you have any events defined:

SELECT * FROM mysql.event;

Or to check event scheduler status:

SHOW VARIABLES LIKE 'event_scheduler';

When including events in your backups:

  • Event definitions may contain sensitive information
  • Events execute with DEFINER privileges
  • Consider reviewing events before restoring them to production