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- é»è®¤ç int ç±»åï¼åå¼èå´æ¯-2147483648-2147483647ä¹é´ï¼è unsigned çåå¼èå´æ¯0-4294967295ä¹é´ã
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AUTO_INCREMENT
CREATE TABLE `test01` (
id int(11) NOT NULL AUTO_INCREMENT PRIMARY KEY,
`name` varchar(60) DEFAULT ''
) ENGINE=InnoDB AUTO_INCREMENT=2147483647 DEFAULT CHARSET=utf8mb4 COMMENT='test01';
INSERT INTO test01(name) VALUES ('test 001');
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select last_insert_id();
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INSERT INTO test01(name) VALUES ('test 002');
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int
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ID èªå¢è¶çæ¶ç解å³æ¹æ¡
æ¹æ¡1) å°intä¿®æ¹ä¸ºint(11) unsigned
ALTER TABLE test01 MODIFY COLUMN `id` int(11) UNSIGNED NOT NULL AUTO_INCREMENT;