LONGTEXT

Complete LONGTEXT type reference: 4GB (2^32-1) storage limit, CHARACTER SET/COLLATE syntax, max_allowed_packet constraints, and JSON/CLOB aliases.

Syntax

LONGTEXT [CHARACTER SET charset_name] [COLLATE collation_name]

Description

A TEXT column with a maximum length of 4,294,967,295 or 4GB (2³² - 1) characters. The effective maximum length is less if the value contains multi-byte characters. The effective maximum length of LONGTEXT columns also depends on the configured maximum packet size in the client/server protocol and available memory. Each LONGTEXT value is stored using a four-byte length prefix that indicates the number of bytes in the value.

JSON is an alias for LONGTEXT. See JSON Data Type for details.

Oracle Mode

In Oracle mode, CLOB is a synonym for LONGTEXT.

EXAMPLES

LONGTEXT

Example of LONGTEXT:

CREATE TABLE longtext_example (
   description VARCHAR(20),
   example LONGTEXT
) DEFAULT CHARSET=latin1; -- One byte per char makes the examples clearer

The maximum size of a LONGTEXT is so large that it cannot be sent to the server without breaking the value up into chunks (something that the command-line client cannot do). For values larger than 16M, you can increase the max_allowed_packet size up to a maximum of 1024M to increase the allowed size of non-chunked values.

INSERT INTO longtext_example VALUES
   ('Normal foo', 'foo'),
   ('Trailing spaces foo', 'foo      '),
   ('NULLed', NULL),
   ('Empty', ''),
   ('Maximum', RPAD('', 4294967295, 'x'));

ERROR 1301 (HY000): Result of rpad() was larger than max_allowed_packet (16777216) - truncated

Data Too Long

When SQL_MODE is strict (the default) a value is considered "too long" when its length exceeds the size of the data type, and an error is generated.

Example of data too long behavior for LONGTEXT:

TRUNCATE longtext_example;

INSERT INTO longtext_example VALUES
   ('Overflow', RPAD('', 4294967296, 'x'));

ERROR 1301 (HY000): Result of rpad() was larger than max_allowed_packet (16777216) - truncated

See Also

• TEXT

• BLOB and TEXT Data Types

• Data Type Storage Requirements

• JSON Data Type

• Oracle mode

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