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The web hosting industry's most reliable management solution since For more information, visit cPanel. Toggle navigation All Blog. You declare the size when you create the table. If you store fewer characters than the fixed length, MySQL pads the remainder with spaces. Therefore, CHAR always consumes the same amount of storage. You specify the maximum length that you intend to store when you create the table. The following sizes assume the database is using the UTF-8 encoding.
This object can be used to store things like short summaries, URL links, and other shorter objects. The standard TEXT data object is sufficiently capable of handling typical long-form text content.
It is sufficiently large enough to hold text for something like an article, but would not be sufficient for holding the text of an entire book. However, BLOB s are binary strings with no character set sorting, so they are treated as numeric values while TEXT objects are treated as character strings. This differentiation is important for sorting information. BLOB s are used to store data files like images, videos, and executables.
For truncation of nonspace characters, you can cause an error to occur rather than a warning and suppress insertion of the value by using strict SQL mode. See Section 5.
Trailing spaces are retained when values are stored and retrieved, in conformance with standard SQL. The values shown as stored in the last row of the table apply only when not using strict SQL mode ; if strict mode is enabled, values that exceed the column length are not stored , and an error results.
InnoDB encodes fixed-length fields greater than or equal to bytes in length as variable-length fields, which can be stored off-page. For example, a CHAR column can exceed bytes if the maximum byte length of the character set is greater than 3, as it is with utf8mb4. The following example illustrates this difference:. NO PAD collations treat trailing spaces as significant in comparisons, like any other character.
See Trailing Space Handling in Comparisons. The server SQL mode has no effect on comparison behavior with respect to trailing spaces.
For additional information about storage requirements, see Section For those cases where trailing pad characters are stripped or comparisons ignore them, if a column has an index that requires unique values, inserting into the column values that differ only in number of trailing pad characters results in a duplicate-key error.
For example, if a table contains 'a' , an attempt to store 'a ' causes a duplicate-key error. Numeric Type Attributes.
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