EC
1624
MySQLWARNINGNotableReplicationHIGH confidence

Unsafe statement: non-transactional table written after transactional table in transaction

Production Risk

High — can cause permanent master/replica divergence.

What this means

Within the same transaction a non-transactional table (e.g., MyISAM) is written after a transactional table (e.g., InnoDB), creating a replication hazard when using STATEMENT mode.

Why it happens
  1. 1Mixing InnoDB and MyISAM writes in a single transaction.
  2. 2If the transaction is rolled back, the MyISAM write cannot be undone, causing master/replica divergence.
How to reproduce
trigger — this will error
trigger — this will error
BEGIN;
INSERT INTO innodb_table VALUES (1);
INSERT INTO myisam_table VALUES (1);
ROLLBACK;

expected output

Warning 1624: Unsafe statement written to the binary log using statement format since BINLOG_FORMAT = STATEMENT.

Fix 1

Avoid mixing transactional and non-transactional tables in the same transaction

Avoid mixing transactional and non-transactional tables in the same transaction
-- Keep MyISAM writes outside InnoDB transactions

Why this works

Separating writes eliminates the mixed-engine transaction hazard.

Fix 2

Convert MyISAM tables to InnoDB

Convert MyISAM tables to InnoDB
ALTER TABLE myisam_table ENGINE = InnoDB;

Why this works

Using a single transactional engine removes the non-transactional write hazard.

What not to do

✕

Sources
Official documentation ↗

MySQL 8.0 — 1624 ER_BINLOG_UNSAFE_NONTRANS_AFTER_TRANS

Content generated with AI assistance and reviewed for accuracy. Found an error? hello@errcodes.dev

← All MySQL errors