Database Administrator

Scenario: The customer said that the OEM was suddenly unavailable. Because the application is linked to some OEM pages, it must be restored immediately. Symptom: Log on to the client server and execute the emctl status dbconsole. An error is

In the clusterware and asm environments of Oracle 11g R2, we will run the Oracle 10g rdbms environment for the purpose of upgrading or migrating data. When using a 10 Gb rdbms to create a database, you must make some adjustments in advance.

There is a new feature in Oracle 11gR2. When the table has no data, no segment is allocated to save space. Oracle cannot export empty tables when executing export, but there is still a solution. Solution: 1. insert a row and then roll back to

1. OS and DB versions Oracle Version: 11.2.0.2 Operation System: HP-UXItanium 11.312. Alert log Information Tue Oct 22:27:31 2012 Exception [type: SIGSEGV, Address not mapped to object] [ADDR: 0xC00000000] [PC: 0x400000000631B880, evaopn3 () + 384] [

Rowid is a pseudo column that uniquely identifies a row in a table. It is the internal address of the row data in the physical table. It contains two addresses. One is the address pointing to the data file that contains the block of the row in the

1. Oracle cannot be started because of reduced memory Last login: Sun Nov 4 15:09:06 2012 from 192.168.5.222[Oracle @ h1 ~] $ Sqlplus "/as SYSDBA" SQL * Plus: Release 11.2.0.1.0 Production on Sun Nov 4 15:26:59 2012 Copyright (c) 1982,200 9, Oracle.

This error occurs ORA-01861: literal does not match format string Statement is Between 'time1' and 'time2' The query result is: ORA-01861: Text and format strings do not match Solution To_date ('time1', 'yyyy-mm-dd hh24: mi: ss ') Or You can

Using dbca to clone an instance does not need to be as tedious as restoring a Data Pump. It is similar to rman in terms of table space creation, User Creation, authorization, copy, and restoration. However, there is still a gap between efficiency

The "SQL" Mark written in the implicit cursor. For example, SQL % ROWCOUNT indicates that the implicit cursor has several rows of records. The explicit cursor is customized by the developer, you can also use C1 % ROWCOUNT to indicate the number of

1. Use the create or replace view command to create a view Syntax format: Create or replace view name As select query clause Example: Create or replace view tb_user_view1 as select count (username) shuliang, username from tb_user group by username

System Environment: CentOS 6.3 Server Windows 7 Client The IP addresses are 10.1.4.44 server and 10.1.4.180 client respectively. 1. Check whether MySQL is installed? [Root @ Web_Mysql ~] # Rpm-qa | grep mysql   2. Install MySQL using YUM: [Root @

System Environment: Database: Oracle 11.2.0.3 (64-bit linux) ArcSDE: ArcSDE9.3.1 sp2 (Build 4000) First, use dbca to create an oracle database instance (AA) Then, use ArcSDE9.3.1 sp2 post oracle 11.2.0.3 to create and configure sde user

Slave processes is the background process that represents the execution of other processes.  I/O Slave Processes I/O slave processes (Innn) simulate asynchronous I/O for systems and devices that do not support it. in asynchronous I/O, there is no

CentOS 6.2 is already installed with mysql 5.1. However, CentOS 5.1 does not support the utf8mb4 character set (For details, refer to:). You can only upgrade Mysql to 5.5. This is indeed a painful upgrade process. Complete steps: 1. First, back up

When reading some posts online. Someone found that the mechanism for organizing and managing database file storage in Sqlite is B-tree. I think this is not rigorous. So I turned out the definitive guide to sqlite SECOND EDITON. After review, I would

I tried to install Oracle 11g R2 under CenOS s5.5 in VMware. I thought it was simple, but I found many problems. Installation steps: 1. check the corresponding rpm package It doesn't matter if the check is complete. It will check the installation of

MySQL multi-Table update can be written in several different ways. Assume that we have two tables. One Table stores Product information for the Product table, with the Product Price column Price. The other table is the ProductPrice table, update the

Operating system version: 64-bit Linux Database Version: Any Version Problem description An error is reported when the database is started after the database parameters are modified. SQL> startup nomount ORA-27102: out of memory Linux-x86_64

The GATHER_TABLE_STATS process of the dbms_stats package is required. The owner and table names must be filled in. PROCEDURE GATHER_TABLE_STATSArgument Name Type In/Out

1. Create two external files in 1.txt and 2.txt with only one data. 2. Create a logical directory and perform proper authorization: SQL> create directory ztj1_dir as 'C: \ ztj1 \'; Directory created Then, manually create the actual directory in the