道行尚浅的道场

某东笔试题

新手版题目1 表A ID NAME AGE 1 张三 27 2 李四 28 ...

Posted by 道行尚浅 on May 8, 2018

使用SQL Access Advisor优化访问路径

SQL Access Advisor 概述 SQL Access Advisor 可以推荐合适的物化视图,物化视图日志,分区,索引等设置,以帮助我们实现性能目标. SQL Access Advisor SQL Access Advisor 使用流程图如下使用范例执行待分析...

Posted by 道行尚浅 on April 12, 2018

使用Oracle STA自动优化SQL

SQL TUNING ADVISOR 简介与架构 STA(SQL Tuning Advisor )是Oracle提供的sql诊断工具.用户可以提交一条或多条SQL 语句到STA,STA会给出建议. 如图所示可以从ADDM AWR SHARED POOL与SQL优化集找到需要优化的SQL...

Posted by 道行尚浅 on March 6, 2018

SQL笔试题

用一条sql语句查出员工工资表所有信息，工资最高的前三条信息按升序排在最前面，其余的按原顺序排列原始数据如下 SQL> select * from scott.emp ; EMPNO ENAME JOB MGR HIREDATE SA...

Posted by 道行尚浅 on January 20, 2018

SQL笔试题

有表A ID VALUE1 VALUE2 100001 10 10 100002 20 20 ...

Posted by 道行尚浅 on January 17, 2018

不用ORDER BY 实现排序

现有如下的表名字省份宝姐黑龙江佛爷吉林道爷吉林翁同学 ...

Posted by 道行尚浅 on January 15, 2018

SQL面试题

题目:一条SQL语句,查处在此间连续三年纳税额超过2000万的企业纳税年份的起止是多少 YEAR ENT AMT 2010 AA 2000 ...

Posted by 道行尚浅 on January 14, 2018

SQL笔试题

题目:已知 “ab”+’ab’=’bcc’ 求a,b,c的值 SQL> with v as (select level c from dual connect by level<=100) 2 select v1.c a ,v2.c b, v3.c c 3 fr...

Posted by 道行尚浅 on January 13, 2018

Redis监控搭建

下载python [root@etlbi ~]# wget https://www.python.org/ftp/python/2.7.8/Python-2.7.8.tgz --2018-01-01 04:15:12-- https://www.python.org/ftp/python/...

Posted by 道行尚浅 on January 12, 2018

单条SQL-字符排序

将字符串’ccbdaefa’ 更改为 aabccdef 即字符串内部按照字符排序 select listagg(c1) within group (order by c1) col from ( select SUBSTR('ccbdaefa',ROWNUM,1) c1 fro...

Posted by 道行尚浅 on January 10, 2018

单条SQL-断层问题

一个连续的数列,从中间删除部分数据,取剩余连续数列的起止位置 create table duan_ceng as select rownum c1 from dual connect by level <=100 ; delete from duan_ceng where...

Posted by 道行尚浅 on January 8, 2018

单条SQL-解蜜芽面试题

蜜芽笔试题: -打印1 22 33 444 555 6666 77777 88888 9999 10101010 1111111111 1212121212 with dao as (select level c1 from dual connect by level <= 5...

Posted by 道行尚浅 on January 7, 2018

Redis 哨兵搭建与管理

主节点操作主节点配置文件 [root@server ~]# cat /master/master.conf daemonize yes pidfile /master/redis6379.pid port 6379 unixsocket /master/redis6379.sock ...

Posted by 道行尚浅 on January 4, 2018

Redis主从搭建实录

主库端操作主库配置文件 [root@bosenrui redis]# cat master.conf #master #general daemonize yes pidfile /redis/redis6379.pid port 6379 unixsocket /redis/redi...

Posted by 道行尚浅 on January 3, 2018

Oracle 11g 自带系统任务研究

概述 Oracle 在创建数据库时有一个选项可选择是否开启自动任务. 默认此选项是勾选的.DBA只是习惯性的勾选这一选项,但对其内容知之甚少. 接下来的文章里,我们将讲解一下自动任务的相关知识. 查看自带任务 SQL> select x.client_name,x.task_nam...

Posted by 道行尚浅 on December 30, 2017

使用10053分析12C分页新特性

SQL> ALTER SESSION SET EVENTS='10053 trace name context forever, level 1'; Session altered. 按工资升序输出雇员信息表的数据 SQL> select * from emp ...

Posted by 道行尚浅 on October 16, 2017

Oracle 分页写法总结

我们在逛一些网站时经常会遇到这种情况,由于返回的数据太多无法在一个页面中完全展示.需要在多个页面中显示.界面类似注意页面的右下角1/33 告诉我们商品一共有33页. 那么这种需求在SQL语句中如何实现?这就是我们经典的分页问题. 其实在这方面Oracle分页写法的复杂程度要高于MySQ...

Posted by 道行尚浅 on August 8, 2017

Oracle分区表详解

分区表概念 1 what 什么是分区 Partitioning enhances the performance, manageability, and availability of a wide variety of applications and helps reduce the to...

Posted by 道行尚浅 on September 12, 2016

MySQL执行计划解析

执行计划收集 DAO_OBJECTS t1 , DAO_OBJECTS t2 WHERE deptno= t1.object_id AND t1.object_name=t2.object_name ; +----+-------------+-------+------+---...

Posted by 道行尚浅 on January 22, 2016

PL/SQL脚本-精确统计表行数

建立表 SQL> create table table_row_count 2 (stat_date date , 3 table_owner varchar2(40), 4 table_name varchar2(40), 5 table_count...

Posted by 道行尚浅 on September 15, 2015