- select * from employees;
- select * form employees where id like ‘&&’ and last_name like ‘&&’;
- select * form employees where id like ‘&&’ or last_name like ‘&&’;(因为是or结果为并集,总会有数据不为null)
结论 :输出结果 1.3一样 2不一样
or 和and 面试题
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转载自blog.csdn.net/hj1997a/article/details/82764951
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