下面两个语句
select phone from user where id >(select id from user limit 3000000,1) order by id limit 0,10;
select phone from user order by id limit 3000001,10;
测试多次,第一个总是比第二个好, 索引都是主键 id 为何会有区别?
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guyeuro OP 顶顶顶!
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