Database Administrator

1. delete mysql Sudo apt-get autoremove mysql-serverSudo apt-get remove mysql-common 2. install Sudo apt-get install mysql-serverSudo apt-get install php5-mysql Configuration: The MYSQL we just installed has only one default root user, and there is

When using expdp to export data in Oracle, sometimes an error occurs. In this case, some records are generated in dba_datapump_jobs. You can see the following command: Select * from dba_datapump_jobs; Now we can see the corresponding JOB_NAME.

I. Operation of sysdate function 1 and sysdateAddition Select sysdate, add_months (sysdate, 12) from dual; -- add 1 year Select sysdate, add_months (sysdate, 1) from dual; -- add January Select sysdate, to_char (sysdate + 7,'Yyyy-mm-dd HH24:

Obtain the DataSet value by page in Oracle.Example:/// /// Obtain the Colletion paging data/// Public DataSet GetList (int PageIndex, int PageSize, string sortExpression, string strWhere){StringBuilder sb = new StringBuilder ();Sb. Append ("select *"

Redo Log BufferThe size is determined by the initialization parameters.LOG_BUFFERThe default value of this parameter isMax (512KB, 128KB * CPU_COUNT). Generally, this default value is sufficient,WeYes, the Redo Log BufferWrite operations are quite

An exception occurs when the maximum number of jdbc cursors is exceeded. The relationship between Oracle and jdbc has been improved. Record it for future reference. If you have any errors, please note. Oralce cursors can be divided into display

Oracle Database 10 Gb provides a significantly improved tool: Automatic Workload information library (AWR: Automatic Workload Repository ). Oracle recommends that you replace Statspack with this. AWR is essentially an Oracle built-in tool that

/* Create Table */Create table A_ybl ( Y INTEGER not null, B VARCHAR (30) not null, L VARCHAR (20) not null );/* Create A backup table for table */ Create table A_ybl2 ( Y INTEGER not null, B VARCHAR (30) not null, L VARCHAR (20) not null );Create

1. Compile the RHEL5.4 Kernel1.1 install software packages Use the yum or rpm command to install the following software package: Gcc-4 .*Gcc-c ++-4 .*Rpm-4 .*Rpm-build-4 .*RedHat-rpm-config-8 .*Unifdef-1 .*Subversion-1 .* 1.2 install the kernel

I used to install MySQL Enterprise Edition in yum in Linux, and I plan to use it recently. I forgot my password. Okay. Record the password retrieval method. 1. Stop all MySQL Processes Killall mysqld 2. Start mysql in Safe Mode Mysqld_safe -- user =

Recently, Oracle 11gR1 was installed on Fedora 14. The database can be normally connected from the local machine, but the connection cannot be established from other hosts.Later I found it was the reason for the firewall. First, run the following

After installing MySQL in Ubuntu, we usually need to set the default Character Set of the database. # First look at the default character set in mysql. # Log on to mysql Mysql-h localhost-u root-p # View character-related attributes Show variables

After a new MySQL connection arrives, a thread is allocated to the thread. If the server has Idle threads cached, use them directly. If no available cache thread exists, re-create a thread for this connection. /*Schedconnection that uses one thread

A source code process for MySQL to receive and execute connection commandsCall Sequence of functions from top to

Select a row of records in the Table: (understanding: rownum is the number of rows sequentially allocated from the query returned by the Oracle System)Select * from (select rownum a, t. * from testtab t) where a = 2;Select * from (select rownum a, t.

Several major Oracle background processes System Monitor SMON restores an instance after it crashes, merges free space in the database, and manages the space for classified operations Process Monitor PMON cleans up faulty user database

RedHat Linux (Fedora Core/Cent OS) 1. start:/etc/init. d/mysqld start 2. stop:/etc/init. d/mysqld stop 3. restart:/etc/init. d/mysqld restart Debian/Ubuntu Linux 1. start:/etc/init. d/mysql start 2. stop:/etc/init. d/mysql stop 3.

The actual instance: Today, I found that the website data was abnormal. I checked the database and encountered the following error when operating a table (tbl_test: Table '. \ mydb \ tbl_test' is marked as crashed and shoshould be retried red You

ServerDELL R410 2Cpu inter E5620. 4 GHz 12M4CMEM 64GDISK 300 GBMemoryDS3512DISK 600G * 12 RAID5(Because JS is shoddy, it took a month to solve the problem on the server fiber optic card.Problem:1. storage cannot be found on the server from time to

JDBC calls the Oracle stored procedure to return the result set and obtain the output parameters: PackageXx. qq. app; ImportJava. SQL. CallableStatement; ImportJava. SQL. Connection; ImportJava. SQL.