SMALLINT
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The parent of this page is: Data Types for MariaDB Enterprise Server
Topics on this page:
Overview
Integer from -32768 to 32767 when signed, or from 0 to 65535 when unsigned.
DETAILS
SYNONYMS
The following are synonyms for SMALLINT:
INT2
EXAMPLES
SIGNED and UNSIGNED
The SMALLINT data type may be SIGNED (allowing negative values) or UNSIGNED (not allowing negative values).
Example of SMALLINT SIGNED (SIGNED is the default):
CREATE TABLE smallint_signed_example (
description VARCHAR(20),
example SMALLINT SIGNED
);
INSERT INTO smallint_signed_example VALUES
('Zero', 0),
('Forty-Two', 42),
('Minimum', -32768),
('Maximum', 32767);
Example of SMALLINT UNSIGNED:
CREATE TABLE smallint_unsigned_example (
description VARCHAR(20),
example SMALLINT UNSIGNED
);
INSERT INTO smallint_unsigned_example VALUES
('Zero', 0),
('Forty-Two', 42),
('Minimum', 0),
('Maximum', 65535);
Out-of-Range
A value is considered "out-of-range" when it is too small or too large to be stored in a data type.
When SQL_MODE is strict (the default) an out-of-range value generates an error. If strict mode is not in effect, the value is rounded to the nearest valid value and a warning is generated (which might be hidden, depending on your warning settings).
An example of non-strict out-of-range behavior:
TRUNCATE smallint_signed_example;
TRUNCATE smallint_unsigned_example;
-- Disable strict mode or the inserts will fail
SET sql_mode=(SELECT REPLACE(@@sql_mode, 'STRICT_TRANS_TABLES', ''));
INSERT INTO smallint_signed_example VALUES
('Underflow', -32769),
('Overflow', 32768);
INSERT INTO smallint_unsigned_example VALUES
('Underflow', -1),
('Overflow', 65536);
Warning (Code 1264): Out of range value for column 'example' at row 1
Warning (Code 1264): Out of range value for column 'example' at row 2
Warning (Code 1264): Out of range value for column 'example' at row 1
Warning (Code 1264): Out of range value for column 'example' at row 2
The resulting data would look like this:
SELECT * FROM smallint_signed_example;
+-------------+---------+
| description | example |
+-------------+---------+
| Underflow | -32768 |
| Overflow | 32767 |
+-------------+---------+
SELECT * FROM smallint_unsigned_example;
+-------------+---------+
| description | example |
+-------------+---------+
| Underflow | 0 |
| Overflow | 65535 |
+-------------+---------+
SMALLINT ZEROFILL
A special type of SMALLINT UNSIGNED is SMALLINT ZEROFILL, which pads out the values with leading zeros in SELECT results. The number of leading zeros are just enough to pad the field out to the length of the type's maximum unsigned value, but the zeros are not included in an expression result or in a UNION SELECT column.
Using SMALLINT ZEROFILL works the same way as SMALLINT UNSIGNED for most operations except a simple SELECT. For example, with the following test table setup:
CREATE TABLE smallint_zerofill_example (
description VARCHAR(20),
example SMALLINT ZEROFILL
);
INSERT INTO smallint_zerofill_example VALUES
('Zero', 0),
('Forty-Two', 42),
('Minimum', 0),
('Maximum', 65535);
-- Turn off strict mode or the inserts will fail
SET sql_mode=(SELECT REPLACE(@@sql_mode, 'STRICT_TRANS_TABLES', ''));
INSERT INTO smallint_zerofill_example VALUES
('Underflow', -1),
('Overflow', 65536);
Warning (Code 1264): Out of range value for column 'example' at row 1
Warning (Code 1264): Out of range value for column 'example' at row 2
The resulting data would look like this:
SELECT *, example + 0 FROM smallint_zerofill_example;
+-------------+---------+-------------+
| description | example | example + 0 |
+-------------+---------+-------------+
| Zero | 00000 | 0 |
| Forty-Two | 00042 | 42 |
| Minimum | 00000 | 0 |
| Maximum | 65535 | 65535 |
| Underflow | 00000 | 0 |
| Overflow | 65535 | 65535 |
+-------------+---------+-------------+
CHANGE HISTORY
EXTERNAL REFERENCES
Additional information on this topic may be found in the MariaDB Public Knowledge Base.