回家的流浪者

2015年3月10日

摘要： Oracle数据库中重复数据怎么去除？使用数据表的时候经常会出现重复的数据，那么要怎么删除呢？下面我们就来说一说去除Oracle数据库重复数据的问题。今天我们要说的有两种方法。一.根据rowid来去重。我们都知道在oracle数据库表中，每条记录都有唯一的rowid来标识,这就可以做我们去重... 阅读全文

posted @ 2015-03-10 17:17 回家的流浪者阅读(4185) 评论(0) 推荐(0)

2015年2月27日

ocp 1Z0-042 121-178题解析

摘要： 121. You want to create a new optimized database for your transactional production environment to be used by a financial application. While creating t... 阅读全文

posted @ 2015-02-27 15:08 回家的流浪者阅读(1384) 评论(0) 推荐(0)

ocp 1Z0-042 61-120题解析

摘要： 61. View the Exhibit.Which statement regarding the dept and emp tables is true?A) When you delete a row from the emp table, you would receive a constr... 阅读全文

posted @ 2015-02-27 15:07 回家的流浪者阅读(2012) 评论(0) 推荐(0)

ocp 1Z0-042 1-60题解析

摘要： 1. Because of a power outage,instance failure has occurred. From what point in the redo log does recovery begin and where does it end?A. Current redo ... 阅读全文

posted @ 2015-02-27 15:06 回家的流浪者阅读(1646) 评论(0) 推荐(0)

ocp 1Z0-043 131-205题解析

摘要： 131. Which three methods can you use to run an Automatic Database Diagnostic Monitor (ADDM) analysis over a specific time period? (Choosethree.)A. Ent... 阅读全文

posted @ 2015-02-27 15:05 回家的流浪者阅读(1830) 评论(0) 推荐(0)

ocp 1Z0-043 61-130题解析

摘要： 61. You are working in an online transaction processing (OLTP) environment. You realize that the salary for an employee, John, has been accidentally m... 阅读全文

posted @ 2015-02-27 15:03 回家的流浪者阅读(2269) 评论(0) 推荐(0)

ocp 1Z0-043 1-60题解析

摘要： 1.You observe that a database performance has degraded overa period of time. While investigating the reason, you find the size ofthe database buffer c... 阅读全文

posted @ 2015-02-27 15:01 回家的流浪者阅读(1880) 评论(0) 推荐(0)

ocp 1Z0-047 131-276题解析

摘要： 131. Which view would you use to display the column names and DEFAULT valuesfor a table?A. DBA_TABLESB. DBA_COLUMNSC. USER_COLUMNSD. USER_TAB_COLUMNSA... 阅读全文

posted @ 2015-02-27 14:55 回家的流浪者阅读(12148) 评论(0) 推荐(0)

ocp 1Z0-047 61-130题解析

摘要： 61. Evaluate the following SQL statements that are issued in the given order:CREATE TABLE emp(emp_no NUMBER(2) CONSTRAINT emp_emp_no_pk PRIMARY KEY,en... 阅读全文

posted @ 2015-02-27 14:54 回家的流浪者阅读(14202) 评论(0) 推荐(0)

2015年2月26日

ocp 1Z0-047 1-60题解析

摘要： 1. You need to load information about new customers from the NEW_CUST table into the tables CUST and CUST_SPECIAL. If a new customer has a credit limi... 阅读全文

posted @ 2015-02-26 16:06 回家的流浪者阅读(11257) 评论(0) 推荐(0)