Database Administrator

1. Installing mysql in Linux is simple.# Apt-get install mysql-server-5.0After installation, set the password. If the password is 'sa' 2. After the installation is complete, log on to the Local Machine# Mysql-u root-pEnter the passwordThis is

To install Oracle in a virtual machine Linux: Step 1: copy the oracle Installation Software to the Linux environment. The specific steps are as follows: in/etc/samba/sam. configure the shared directory in conf. First, you need to create a new folder

The two highly lethal commands compiled today can instantly kill Oracle. Next I will give a simple comment and demonstrate its power.$ Ps-ef | grep $ ORACLE_SID | grep-v grep | awk '{print $2}' | xargskill-9$ Ipcs-m | grep oracle | awk '{print $2}' |

A system suddenly loses power, and Oracle cannot be started after the system is started. The following error is reported during startup: ORA-01102 cannot mount database in EXCLUSIVE modeError 1102 may be caused by the following possibilities: 1. In

The network is disconnected and the DBConsole service cannot be started to solve this problem. Many Oracle 10 Gb XDJM users have encountered this problem. I have also encountered this problem in my notebook. DBConsole is usable, however, if a laptop

A. hardware configuration requirementsThe minimum hardware configuration required for installing Oracle 9i is as follows:Memory: 512 MBSwap space: 1GDisk space: Database software: 3.5G; seed database: 1GTemporary disk space: 400 MB in/tmp1. If swap

1. Obtain the length of a table row record in Oracle under a user This length is the length defined by the table field. How to obtain it: SelectOwner, Table_name, Column_name, Data_type, Data_length, Sum(CaseData_type When 'Date' Then  7

1. view the table space name and size. Select t. tablespace_name, round (sum (bytes/(1024*1024), 0) ts_size From dba_tablespaces t, dba_data_files d Where t. tablespace_name = d. tablespace_name Group by t. tablespace_name;　　 2. view the name and

Because there is no description of the software package in rh5 in Oracle10.2 official documentation, the installation is based on the AS4 package, but the following error is returned today to help you get an error when downloading 10 Gb in RH5: /tmp/

After logging on to a new company and receiving a new notebook from the asset department, Problem 1: the scott user cannot log on. the prompt is [the user was locked !]; Question 2: The sys user password is missing. Solution: (1) In "run", use

Value Type MySQL includes strict data types (INTEGER, SAMLLINT, DECIMAL, NUMERIC), and approximate data types (FLOAT, REAL, DOUBLE). After extension, TINYINT is added, MEDIUMINT and BIGINT types have different lengths, and BIT types are added to

Oracle version: 10.2.0.2 with data guardOperating System: linux rhat 5.6x64 Recently, the oracle alert Log of the master database found that the ora 600 error occurs almost every day in the last half month, as shown below:Errors in file/oracle/admin/

According to the morgo suggestion suggested by morgo, I did some small tests on the queries and datasets mentioned in Impact of column types on MySQL JOIN performance, but I found another problem: response time (aka MySQL versions ).The answer To

Important DB log concepts $ db2 get db cfg for sampleLog file size (4 kb) (LOGFILSIZ) = 1000 Number of primary log files (LOGPRIMARY) = 3 Number of secondary log files (LOGSECOND) = 2 Changed path to log files (NEWLOGPATH) = Path to log files =/home/

Oracle 11gR2 Single Instance database boot self-start 1. Change the N at the bottom of/etc/oratab to Y. 2. Modify $ ORACLE_HOME/bin/dbstart and $ ORACLE_HOME/bin/dbshut. ORACLE_HOME_LISNER = $ absolute path of ORACLE_HOME 3. added as a linux service:

Recently I just changed my job, but fortunately, I am still working on Database O & M. What is depressing is that the upgrade is shared. The background error is reported! First let's talk about ora-00020 error! We all know the reason is that the

The following error occurs when rman is used for restore: Channel c1: ORA-19870: error while restoring backup piece/u01/dbfull_03orat5q_1_1.bakORA-19502: write error on file "/u01/app/Oracle/oradata/aux/system01.dbf", block number 34304 (block size =

When using Maven to build a project, it will certainly involve adding the Oracle database driver dependency. However, it is difficult to find Maven dependency configuration in the Maven repository. Currently, it seems that only the Oracle10g

Oracle RAC upgrade test is performed in the test environment today. The original version is 11.2.0.3.0 and you want to upgrade it to 11.2.0.4.0, however, during the runinstaller process, [INS-06006] Passwordless SSH connectivity not set up between

Indexing null values Install relational database theory. null indicates unknown. Oracle B-tree index does not contain null. Consider the following table: Create table tt (t_id number, t_name varchar2 (10 ));Create index tt_idx on tt (t_name