Database Administrator

Oracle uses a cursor to delete all record scripts in all user data tables Application Scenario: because the data in the Oracle database involves confidential information, we hope to delete all the data at a time and only keep the data table

Use Sqoop to import MySQL Data to Hadoop The installation and configuration of Hadoop will not be discussed here.Sqoop installation is also very simple. After Sqoop is installed and used, you can test whether it can be connected to mysql (Note: The

Configure Oracle data sources in JBoss 7 I. jboss7 directory structure In JBoss 7, the file system is divided into two parts: 1. Independent Server 2. Domain Server (first introduced in JBoss 7)-used for unified management of multiple instances BIN:

Use the snapshot feature of LVM to implement almost hot backup of data The snapshot function of LVM can record information at a certain time point to the snapshot area. Therefore, you can use this feature to completely back up data. Then, the new

SQL Server Authentication and user logon, SQL Server During installation, the SQL Server database engine is set to "Windows Authentication Mode" or "SQL Server and Windows Authentication mode ". After installation, you can change the Authentication

Wet shoes yesterday... yesterdayAt the customer's requirement yesterday, several tables were added to the synchronization scope of ogg.I checked the dp process, the rep process, and confirmed that the two processes do not have these tables. Then I

Mysql primary key auto-increment and default value, mysql Default Value Create table 'ecm _ address' ('addr _ id' int (10) unsigned not null AUTO_INCREMENT, 'user _ id' int (10) unsigned not null default '0 ', 'consignee' varchar (60) not null

Two ways to improve performance using direct-path insert: direct-pathinsert1. Traditional serial insert There are two common insert methods: (1) insert into table_name values (....) (2) insert into target_table select * from source_table The above

SnappyDB-NoSQL database on Android, snappydbnosql Or starting from the demand. When developing an App, you often need to cache some data so that it is not empty every time you open the App. You need to download data from the network. For example, a

MySQL-10-mysql programming, linuxmysql Programming MySQL Programming 1. Statement Terminator There are two default values:; and \ g (which can only be used in the command line) You can use the delimiter command to modify the statement Terminator,

Mssql Job, mssql 1. What is a job? A job is a series of specified operations performed by the SQL Server Agent in sequence. A job can execute various types of activities, including running Transact-SQL scripts, command prompt applications,

Mysql database optimization summary and mysql database Summary I. Common Database optimization operations 1. The table design must conform to the three paradigm. 2. Add an appropriate index, which has a great impact on the query speed. You must add

[Synchronous replication common error handling 3] The Stored Procedure sp_MSins_tablename cannot be found, and the stored procedure cannot be found An error occurred while synchronizing the environment to SQL2008 R2 The error message is that the

Mysql encounters an error similar to "Every derived table must have its own alias ". Every derived table must have its own alias This statement means that each derived table must have its own Alias. This error occurs when multiple tables are queried.

SQL query operation process and SQL operation processHere we can see the Query Processing of SQL in the book. In SQL, the query is achieved through the select statement and some auxiliary clauses. Here mysql is used. First, to understand the

SQL two simple paging query methods, SQL paging Query Method In the past, we may have used the skip and take method of linq for paging queries, but few of them write SQL paging queries by themselves, because most of the time, we are calling others'

Failed to upgrade Oracle Cluster Registry configuration, raccluster during 10g rac Installation Failed to upgrade Oracle Cluster Registry configuration was encountered during 10g rac installation, because the BUG was triggered by using the DMM multi-

Overview of the Online Redo Log, overviewredo For oracle restoration, the most important data structure is the online redo log (online redo log). The online redo log contains at least two pre-allocated files used to store database changes. Online

Oracle Partition Table execution plan, oracle execution plan Partition tables have many advantages: they are big, small, and small. With parallel use, loap can often improve the performance by dozens or even hundreds of times. Of course, poor table

SQL stored procedures update data through multiple IDs, SQL stored procedures The following is an example: I want to add 1 to the name of some brands (that is, Brand_Name), and Brand_ID is the primary key. The SQL statement is easy to implement. But