Database Administrator

If you suspect that computer hardware is the main cause of affecting the Performance of SQL Server, You can Monitor the load of the corresponding hardware through SQL Server Performance Monitor to confirm your guesses and identify system bottlenecks.

1. First, decompress the mysql-noinstall-5.2.3-falcon-alpha-win32.zip package in the E drive and change it to Mysql, which is placed in the root directory of the E drive. 2. Create a new "my. ini" file in notepad and enter [WinMySQLAdmin]Servers =

I. constraint operations1: Change the constraint name:Alter table TName rename constraint oldname TO newname;2: delete ConstraintsAlter table TName drop constraint cname3: Stop ConstraintsAlter table TName modify constraint cname DISABLE;4:

To view the available RAM and swap space, run the following command:Grep MemTotal/proc/meminfoGrep SwapTotal/proc/meminfoFor example:# Grep MemTotal/proc/meminfoMemTotal: 512236 kB# Grep SwapTotal/proc/meminfoSwapTotal: 1574360 kBNext, create a

I. gb2312, gbk, utf8, and other character sets supporting multi-byte encoding can store Chinese characters. The number of Chinese Characters in gb2312 is much smaller than that in gb2312, while that in gb2312 and gbk can be encoded in utf8.2. Run

In actual Oracle applications, many people may encounter such problems. For performance or other considerations, you need to change the tablespace of a table or all tables of a user. The common practice is to first Delete the table and then

The maximum number of connections in MySQL is 100 by default.Client Logon: mysql-uusername-ppasswordSet the new maximum number of connections to 200: mysql> set GLOBAL max_connections = 200Display the currently running Query: mysql> show

I. Preparations1. Check component InstallationIf it is fully installed, the system only has two patches compat-libcwait-2.0-2.i386.rpm and compat-Oracle-rhel4-1.0-5.i386.rpm,If not, check whether many components are installed.The following are

I. Summary ① MySQL features Efficient and stable, open source code, multi-user support, multithreading, openness, extensive application support, transaction processing, big database processing, high flexibility, security permission and password

Oracle 10gR2 in Solaris 10 is automatically started upon startup 1. Modify the/var/opt/oracle/oratab file. The following dbstart and dbshut start the database based on the file: Orcl:/opt/oracle/product/10.2: Y 2. Modify the $

Turning off data prompts Oracle ORA-24324 ORA-01041 ORA-01089 errors and personal resolutions. SQL> conn/as sysdbaConnected to an idle instance. SQL> shutdown immediateThe ORA-24324: service handle not initialized.ORA-24323: value not allowedORA-0108

Symptom: After the Grid is installed to the last step, the root script on both sides is also executed, and the INS-20802 error is reported. From the error symptom, no problem is found and a prompt is displayed to view the. log file. Log File

Background description:Create a catalog database in the rman environment. Problem:The following error message is displayed when you register a catalog database on the target machine: RMAN> register database; PL/SQL package RMAN. DBMS_RCVCAT version 1

An error is prompted when you start database listening today: TNS-12545: the connection failed because the target host or object does not existTNS-12560: TNS: protocol adapter error.TNS-00515: the connection failed because the target host or object

Oracle contains three parts: 1: Oracle Server: An Oracle Server. Generally, it can be seen as a machine. We can call it a Server. It can also be seen as a set of software running on the server. It is defined on the official Oracle website as follows:

Public Network: provides external services for connecting clients, application systems, and databases. In addition to database maintenance, users seldom directly connect to the database,A common practice is to connect a user to a database through

This article mainly verifies the maximum available space size of the lvm + raw device tablespace. -- 1. Prepare the tablespace before it is created. The size of/dev/raw/raw14 is 8 Mb.[Oracle @ master ~] $ Ln-s/dev/raw/raw14/oracle/oradata/rawt/test01

Introduction:---Oracle Statspack was introduced from Oracle8.1.6 and immediately became a powerful tool used by DBAs and Oracle experts to diagnose database performance. Through Statspack, we can easily determine all the bottlenecks of the Oracle

Problems FoundThe top command checks the server load and finds that mysql often has more than 90% CPUs. The cause of this high Mysql load is probably mainly caused by index problems and some abnormal SQL statements.Troubleshooting1. determine the

When the application fails, it runs up and finds that the application interface has always reported a wrong logon database user and password. After checking that the Oracle database is restarted, the user name and password policies exceed the