Database Administrator

Dex is an open-source MongoDB optimization tool. It analyzes query logs and current database indexes and proposes efficient index optimization policies to administrators.Quick Start Installation pip install dexStart monitoring dex -f mongodb.log

Oracle retrieves data for a certain period of time: Sysdate + 1 is plus a day, sysdate +/-(1/48) is plus/minus half an hour Select count (*) from table_name where table_name.date between to_char (sysdate-1/48, 'yyyymmdd HH: Mi') and sysdate Date

Requirements for Oracle 11.31 database installation on HP-UX IA64 10.2 systems: I. Swap memory requirements If RAM is 1024 MB to 2048 MbThen 1.5 times RAMElseif RAM & gt; 2048 MB andThen match RAMElse RAM> 8192 MBThen. 75 times RAM Ii. JDK

Error Code 1 in the slave log: [ERROR] Error reading packetFromServer: Client requested masterToStart replicationFromImpossible position;LastEvent wasRead From 'Mysql-bin.20.16' At455562731,LastByteReadWasRead From 'Mysql-bin.20.16' At4.

1. Install cmake first.# Tar zxf cmake-2.8.3.tar.gz# Cd cmake-2.8.3/#./Bootstrap & gmake install 2. Install mysql# Groupadd mysql# Useradd-g mysql-s/sbin/nologin# Mkdir-p/data/mysql # Chown-R mysql. mysql/data/mysql # Chmod 755/data/mysql # Tar zxf

View login users:You can:Show user;Select sys_context ('userenv', 'session _ user') from dual;Select user from dual; View all login users must be DBA users:Select username from v $ session;DBA users such as sys and system View objects (tables) in

Java. SQL. SQLException: Access denied for user 'root, password = www.bkjia.com '@ 'localhost' (using password: NO) Today, when I tried to write the code for connecting to the database, I encountered a problem. It took only half a day to find the

Recently to http://forge.mysql.com/worklog/task.php? The binlog pre-allocation mentioned in id = 4925 is implemented based on percoan5.5.18. In worklog, the tps is increased by 10 times when sync_binlog = 1. It is indeed possible that no group

When running a 32-bit Oracle database on a 32-bit or 64-bit platform, SGA is always limited, so that large memory machines cannot fully play a role, recently, I have found some documents on adjusting the largest SGA region. I have read the documents

When you use sqlite3 to insert data, it takes about ms to insert each data entry. For batch import, You can import things to increase the speed. But assuming that your business inserts several data records every several seconds, Ms is obviously not

I recently found a problem with Oracle11g. I will discuss it with you. Is in Oracle 11.2.0.3 For Linux X64 environment. Check whether the database has the LOCK information. When querying the V $ LOCK view, we found that there was no response for a

RangePartition: RangeA partition is a table partition with a wide range of applications. It uses the range of column values as a partition condition to store records to column values.RangePartition. For example, by time,2010Year1Monthly

Determines whether to use spfile or pfile when Oracle is started. The default initialization file used after Oracle 9i is spfile. We can use the following three methods to determine whether it is SPFILE or PFILE to start the database.1. show

Delete diskgroup on an Oracle 11g ASM instance. An error occurred while deleting the ORA-15027: active use of diskgroup precludes its dismount, as shown below: SQL> drop diskgroup webdg including contents; Drop diskgroup webdg including

1: List the names, department names, and salaries of all employees. Select a1.ename, a1.sal, a2.dname from emp a1, dept a2 where a1.deptno = a2.deptno; 2: List detailed information about all departments and number of departments Select a2.deptno, a2.

Install MySQL in Ubuntu To install MySQL, run the following command at a terminal prompt: Sudo apt-get install mysql-server mysql-client # midway will let you enter a root user password sudo apt-get install php5-mysql # installation php5-mysql is to

I. Oracle cluster architecture Oracle RAC is the Real Application Cluster of Oracle. It is a parallel Cluster system provided by oracle. The entire Cluster system is composed of Oracle Clusterware (Cluster ready software) and Real Application

This week, two sets of EMC storage are migrated, and several intranet database servers are attached to the storage space. You need to migrate the stored database to the server. The specific migration steps are as follows: I. Environment: 1. original

Oracle implicit parameter: Use of allow_resetlogs_uption Tip: Implicit parameters of Oracle should be used only in the test environment or with the Support of Oracle Support. When the redo file in oracle is corrupted:1: If the damaged non-current

In Oracle databases, the tools used to execute scheduled tasks are generally DBMS_JOB packages. This package is easy to use and has a long history and is still widely used. Frankly speaking, this package's functionality satisfies the scheduling task