Data truncated for column

What this means

Warning (or error in strict mode) 1265 is generated when a value being inserted or updated is silently truncated to fit the column definition — for example, a string too long for an ENUM, a decimal with too many fractional digits, or a value outside an integer range. In strict SQL mode this becomes a hard error.

Why it happens

1. 1Inserting a string value into an ENUM column that does not match any ENUM member
2. 2Inserting a DECIMAL value with more fractional digits than the column definition allows
3. 3Inserting a value into a SET column that is not a recognised member
4. 4String value exceeds column length when strict mode is off (truncated silently)

How to reproduce

Inserting an invalid ENUM value with strict mode disabled.

INSERT INTO orders (status) VALUES ('shipped_today');
-- status is ENUM('pending', 'shipped', 'delivered')

Fix 1: Enable strict SQL mode to make truncation a hard error

In all production environments — strict mode prevents silent data corruption.

SET SESSION sql_mode = 'STRICT_TRANS_TABLES,NO_ZERO_DATE,NO_ZERO_IN_DATE,ERROR_FOR_DIVISION_BY_ZERO';
-- Or permanently in my.cnf:
-- sql_mode = STRICT_TRANS_TABLES,...

Fix 2: Fix the source data to match the column definition

When the value being inserted is incorrect.

-- Map to a valid ENUM value before inserting:
INSERT INTO orders (status) VALUES ('shipped');

-- Or extend the ENUM to include the new value:
ALTER TABLE orders MODIFY status ENUM('pending', 'shipped', 'shipped_today', 'delivered');

What not to do

Version notes

Sources

Confidence assessment

See also