CREATE TABLE ALLITEMS( itemid INT(10)UNSIGNED, itemname VARCHAr(50));ALTER TABLE ALLITEMS CHANGE itemid itemid INT(10)AUTO_INCREMENT PRIMARY KEY;DESC ALLITEMS;INSERT INTO ALLITEMS(itemname)VALUES ('Apple'), ('Orange'), ('Banana');SELECt *FROM ALLITEMS;我之前也对
CHANGE和
MODIFY关键字感到困惑：
ALTER TABLE ALLITEMS CHANGE itemid itemid INT(10)AUTO_INCREMENT PRIMARY KEY;ALTER TABLE ALLITEMS MODIFY itemid INT(5);
在此期间，还请注意，
AUTO_INCREMENT也可以以预定义的数字开头：
ALTER TABLE tbl AUTO_INCREMENT = 100;
