Database Administrator

When the Oracle archive log is full, you cannot log on to Oracle normally. You must delete some archived logs to log on to Oracle normally. 1. Delete physical files of archived logs. archive logs are generally stored in the archive directory. The

Today, a developer asks a question about not exists. Let's make an experiment. Lab 1 SQL> select * from emp e1 where not exists (select 1 from emp e2 where e1.mgr = e2.empno );EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO------------------------------

This error often occurs in Oracle data after an illegal shutdown: EXP-00056: ORACLE error 1033 appearsORA-01033: ORACLE initialization or shutdown in progressUser:Password: This is obviously because the database cannot be started, but the database

A transaction is a logical unit of work used to separate database activities. A transaction has a starting point and an ending point;When one of the following events occurs, the transaction starts: Connect to the database and execute the DML

A Data Type in PHP is very important. It is an associated array, also known as a hash table. It is a very useful data structure.In the program, we may encounter the problem of removing duplicates. The simplest model is as follows:There is a list of

Select SYSDATE from dual t; -- system dateSelect TO_CHAR (SYSDATE, 'yyyy/MM/DD HH24: MI: ss') from dual t; -- format the dateSelect TO_DATE ('2014 18:28:20 ', 'yyyy/MM/DD HH24: MI: ss') from dual t; -- format the dateSelect sysdate, sysdate-interval

1. Processing Run rcv11i_sa. SQL with reference to Note: 402245.1. Enter the po number, and the remaining values are default. Refer to Note: 1294177.1. If there is a problem with the above script, you can download the script from this Note to find

I have created a new user named watson and granted the related priviledges as following: SQL> create user watson identified by watson; SQL> grant resource, connect, create session to watson;   There will be an error happened when we use this new

Note: 1. The fixed-length character type occupies more space than the non-fixed-length character type, but the fixed-length character type does not need to be processed during field value setting, therefore, the processing speed is faster.

I can't help myself. My R & D colleagues directly shut down the plug-in power supply when testing the IBM 3650 server ??? The next day, after some restart, oracle opened the error ORA-00600: internal error code, arguments: [4194], [53], [41], [], []

4. Which two statements are true regarding single row functions? (Choose two .) A. They a ccept only a single argument. B. They can be nested only to two levels. C. Arguments can only be column values or constants. D. They a lways return a

Use the exact numeric data type of integer data.BigintInteger Data from-2 ^ 63 (-9223372036854775808) to 2 ^ 63-1 (9223372036854775807) (All numbers ). The storage size is 8 bytes.IntInteger Data from-2 ^ 31 (-2,147,483,648) to 2 ^ 31-1 (2,147,483,64

10. View the Exhibit and examine the structure of the PROMOTIONS table. Each promotion has a duration of at least seven days.Your manager has asked you to generate a report, which provides the weekly cost for each promotionDone to l date.Which

Chapter 1 Basic SQL statements1. query the database system time, which is usually displayed in the default format of the server (depending on the character set of the database );Note: dual is a virtual table in the database and belongs to the

Part 1 Database SQL language Empty rows and spaces in database scripts     In database scripts, empty rows and spaces play the "icing on the cake" role. Using them appropriately can improve the Code standardization and readability, and thus improve

When PowerDesigner is used, the font size and color of the default table are very difficult to see. If you set the font color through Symbol ---> Format, you can only modify the selected most and the newly created Table is invalid. You can modify

Zookeeper manages voting disks 1. Some things that must be known about voting disk:We can use the dd command to back up voting disk before 11g, But oracle no longer supports using dd to back up voting disk after 11g.If the dd or cp command is used,

Introduction to Oracle elastic uard  I. Basic principles of DataGuard When a transaction changes the data in the production database, the Oracle database records the change in an online redo log file. You can configure the log Writing Process in the

You can query from v $ SQL or v $ sqlarea in a short period of time. If you want to query within a week or a month, you may not be able to find it in V $ SQLAREA! The following is obtained through history DBA_HIST_SQLSTAT, Which is retained through

/** Normal paging * 10 records at 1000000 offset on the data file */select * from zol1__92game_net_ecms_bjwhere classid = 303 order by id ASCLIMIT limit, 10; /** efficient paging * 1. Search for the starting Index * 2. Search for 10 results from the