Database Administrator

Install MariaDB (MySQL) on CentOS 6.5) Install MariaDB (MySQL) on CentOS 6.5) 1. Get the installation package of mariaDB from the official website and put it under the root directory through xftp. 2. Expand the MariaDB File Tar xf

Parameter Adjustment when deploying MongoDB Deploy the MongoDB production server and give the following suggestions: Use a virtualized environment; System Configuration 1) recommended RAID configuration RAID (Redundant Array of Independent Disk,

Restore the backup set created by mysqldump Restore the backup set created by mysqldump: SQL format recovery Create a table structure first Method 1: [Mysql @ mysql1 ~] $ Mysql-usystem-p123456-S/data/mysqldata/3306/mysql. sock hugc Method 2:

Start the SQL Server service with bat I declare that this SQL Server Service script was not written by me. I forgot where I saw it. I will share it with you here, because in my understanding, the technology is used for sharing, don't mind if the

A ORA-03262 is reported when an empty datafile is deleted from tablespace Reference: Cannot Drop Empty Datafile From Tablespace ORA-03262 (Document ID 1353029.1) Applicable: Oracle Server-Enterprise Edition-Version: 11.2.0.2 and later [Release: 11.2

Oracle start command The start command can read the content in the file to the buffer, and then run the content in SQL * PLUS. the syntax of the start command is as follows:Start {url | file_name}The url is used to specify a url address, such as

Compile and install MySQL in Linux Recently I want to develop Hadoop, install MySQL, and test sqoop. Since MySQL is open source code, install it in source code. The following describes my test environment: VMware10 + Ubuntu14.04 Kylin Next, let's

SQL DCL Data Control Language, used to define access permissions and security levels;, sqldcl DCL   1. Create a user * Create user username @ IP address identified by 'Password '; > You can only log on to the specified IP address. * Create user

Before dropping a user, we recommend that you obtain the user's dependency. Before deleting these two users, we recommend that you obtain their dependencies: SQL> col owner format a15SQL> col name format a15SQL> col REFERENCED_NAME format a30SQL>

Oracle object type Oracle object typeObject Type In PL/SQL, object-oriented programmers are based on object types. The object type is a user-defined Composite data type. It encapsulates the data structure and processes and functions used to

CBO Full Table Scan, cbofulltablescan Reprinted please indicate the source: http://blog.csdn.net/guoyjoe/article/details/44261859 **************************************** *******I. Full Table Scan-FTS algorithm of CBO*********************************

Javaee-jdbc, javaee 1. First import the jdbc-mysql package 2. Program Framework: 3. Database Configuration File Driver = com. mysql. jdbc. DriverUrl = jdbc: mysql: // localhost: 3306/jdbc_dbUsername = rootPassword = 1234 4. Access the underlying

Oracle archive and non-archive Modes Oracle archive mode and non-archive Mode settings The log archiving mode of Oracle can effectively prevent instance and disk faults and is indispensable for database fault recovery. Because the initial

Oracle views the properties of a tablespace, modifies the tablespace status, and oracle viewsThe status attributes of a tablespace mainly include online, offline, read only, and read write, the read-only and read/write statuses are special online

Mysql char varchar blob text performance details, varcharblob Char Fixed Length, up to 255 bytes. If the storage space is not full, a space will be filled on the right side of the data. Varchar The maximum length is 65536 bytes. When the varchar

Install mysql in CentOs Rpm (hands-on instruction) and centosrpm First, upload the mysql-rpm package flashFXP required for rpm installation to/usr/local/ : Link: http://pan.baidu.com/s/1i3rb2Gt password: 5pk8 1: # file/sbin/init // check that

Nvl function usage, nvl Function A nvl function is a null value conversion function.NVL (expression 1, expression 2)If expression 1 is null, NVL returns the value of expression 2. Otherwise, expression 1 is returned. The purpose of this function is

Modify instance SID in Oracle and instance sid in oracleModify the ORACLE Instance nameSystem Environment: CentOS 6.5ORACLE version: 10.21. Check the original database instance name$ Echo $ ORACLE_SIDOrcl$ Sqlplus/as sysdba> Select instance from v $

Atitit. automatically generate a database structure script or change the database, based on hibernate4, atitithibernate4 Atitit. automatically generate the database structure script or change the database, based on hibernate4   Current situation ::  

Mysql-one of slow query logs, Mysql-one of slow logsSlow query log1. When no results are returned after a certain period of time, the slow query log is recorded.2. Slow query logs can help DBAs find SQL statements with slow execution efficiency and