Database Administrator

Hadoop 2.2, hbase0.94.18 cluster installation, hadoophbase0.94.18 Here we install three clusters: Cluster ip Address: 192.168.157.132-134 Master: 192.168.157.132 Slaves: 192.168.157.small-134 Hbase depends on zookeeper for self-installation. 1.

T_ SQL rowtype, t_sqlrowtype T-SQL formats: Declare Statement Begin Processing End -- complete   Nvl function nvl (string, value ); Returns a string if the string is not empty. Returns the value if the string is null.   Enter a job

Drop goldengate user times ORA-00604 ORA-20782 ORA-06512 problems resolved, ora065121. Problem SQL> drop user goldengate cascade; When Drop goldengate user, the ORA-00604 ORA-20782 ORA-06512 error is reported, the specific error content is as

Oracle cursor introduction, Oracle cursor IntroductionOracle cursor Introduction The PL/SQL cursor in Oracle stores the data queried in the database in the memory as a temporary table. The cursor can operate on the data stored in the memory, one or

Oracle 11g adds a control file to the ASM disk, 11 gasm A Control File is one of Oracle physical files. It records the database name, data File location, and other information. The importance of the control file is that the database will go down

Redis persistence-AOF, Redis persistence-AOF Redis's persistent AOF mode records every write operation processed by the server in the form of logs. When the Redis service starts, it reads the file to re-build the database, to ensure that the data in

Hot modification of Redis configuration parameters and redis configuration parameters Redis uses configCommand to hot modify configuration item parameters without restarting. RedisIt is recommended that you do not restart the instance. A restart

Linux mysql regular backup and compression, linuxmysql 1. Check whether the mysql BACKUP command works. Create a backup directory under the var directory and a mysql directory under the backup Directory to store mysql backup files Cd to

SQL Server Service Remote process call failed, SQL Server call Due to the need for a unified vs version for the development system, after a hard and arduous struggle all day yesterday, xiaobian finally succeeded in writing in the 13 version of vs

Filesystemcache and aixfilesystemcache on aix The filesystemcache on aix has been discussed in the following books:   The Oracle optimization Diary of eel: The story of a gold card dba. See page 165th:   This FileSystemCache, after nmon enters,

Centos MySQL5.6 installation method, centosmysql5.6 1. download rpm package Determine the system version first [Root @ xcldtc5m/] # cat/proc/versionLinux version 2.6.32-431. el6.x86 _ 64 (mockbuild@c6b8.bsys.dev.centos.org) (gcc version 4.4.7 2012031

Oracle having, oraclehaving The HAVING clause is added to SQL because the WHERE keyword cannot be used with the aggregate function. Syntax:SELECT column_name, aggregate_function (column_name)FROM table_nameWHERE column_name operator valueGroup by

Oracle's problem about number type conversion to_char is that oracleto_char Select to_char (0.1) nums from dual; It is observed that if the integer of a decimal number is 0 and the preceding 0 is not displayed after the string is converted, and

Highlights of Centos mysql operations, centosmysql Problem: 1. The problem [root @ rekfan mysql] # service mysql restart occurs.MySQL server PID file cocould not be found! [Failed]Starting MySQL... The server quit without updating PID file

IMP cross-platform Migration Database SQL generation SQL method tablespace creation script, impsql When using EXP/IMP for cross-platform migration, we need to manually create the tablespace and data files consistent with the source at the target end

Test SQL left join on and where efficiency, sqljoin Recently, many of my predecessors used left join on, so I checked it online for a long time. I felt that it was not great. So I tested it. Although not rigorous, it has already reflected general

Batch import xml to the shell script in informatica repository and shell batch comment The objectimport command of pmrep is mainly used. When executing this command, you need to configure control file (xml file, configure some import parameters and

ORA-14551: cannot perform a DML operation inside a query, ora-14551dml The ORA-14551: cannot perform a DML operation inside a query will be reported when the insert operation is performed in the Oracle Function Cause: Functions that have write

Use of mysql innodb on Openwrt and related exceptions, openwrtinnodb First, configure mysql in menuconfig, specifically in Utilities-> database-> mysql-server. In this way, you can compile it directly. However, innodb Storage engine is not supported

View the table structure in mysql, and view the table structure in mysql Query the table structure under the Mysql shell command line: 1. desc (description) commandDesc tablename; Describe tablename; 2. show command Show columns from