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  • Oracle分页查询


    =====================
    mysql
    =====================
    select * from table_name limit 从第几条取,取几条

    =====================
    sql server
    =====================
    select top 4 * from 表名 where not in(select top 4 * from 表名 where 条件);
    排除前4条,再取4条

    =====================
    oracle
    =====================
    --第一层
    select * from emp;
    --第二层
    select t1.*,rownum rn from (select * from emp) t1 where rownum<=12;
    --第三层
    select t2.* from (select t1.*,rownum rn from (select * from emp) t1 where rownum<=10) t2 where t2.rn>=6;

    int startIndex; 开始位置
    int pageSize; 取的条数
    select t2.* from (select t1.*,rownum rn from (select * from emp) t1 where rownum<=(startIndex*pageSize)) t2 where t2.rn>=((startIndex-1)*pageSize+1);

    测试:
    --创建新表查入另一张表的数据
    create table mytest as select empno,ename,job,sal,comm from emp;
    --自我赋值数据[多次执行]
    insert into mytest(empno,ename,job,sal,comm) select * from mytest;

    select t2.* from (select t1.*,rownum rn from (select * from emp) t1 where rownum<=10) t2 where t2.rn>=6;
    select t2.* from (select t1.*,rownum rn from (select * from emp) t1 where rownum<=300010) t2 where t2.rn>=300000;

    分别查看所执行的时间

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  • 原文地址:https://www.cnblogs.com/qintangtao/p/2746727.html
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