1954
MySQLERRORCriticalSchemaHIGH confidence
Table upgrade required. Please run "REPAIR TABLE `%s`" or dump/reload to fix it
Production Risk
High — table is inaccessible until upgraded.
What this means
A table was created with an older file format that is not compatible with the current MySQL version. MySQL refuses to open the table until it is upgraded.
Why it happens
- 1Table created with MySQL 4.x or earlier MyISAM format opened in MySQL 5.x+.
- 2Table file format is obsolete and not supported by the current storage engine version.
How to reproduce
trigger — this will error
trigger — this will error
SELECT * FROM old_format_table; -- triggers error on open
expected output
ERROR 1954 (HY000): Table upgrade required. Please do "REPAIR TABLE 'old_format_table'" or dump/reload to fix it.
Fix 1
Run REPAIR TABLE
Run REPAIR TABLE
REPAIR TABLE old_format_table;
Why this works
REPAIR TABLE rebuilds the table in the current format.
Fix 2
Dump and reload the table
Dump and reload the table
-- Dump: mysqldump db old_format_table > table.sql -- Reload: mysql db < table.sql
Why this works
Exporting and reimporting recreates the table in the current format.
What not to do
✕
Sources
Official documentation ↗
MySQL 8.0 — 1954 ER_OLD_FILE_FORMAT
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