Database Administrator

How to view the usage of some commands in SQL * plus Sometimes I forget the usage of some commands when using SQL * plus. In fact, we don't have to look up anything. We just need to check it in SQL * plus, Use help |? Parameter For example, in SQL *

Notes for new SQL Server database DBAs Any optimization or modification is based on the business situation. You are welcome to make a picture of what may be wrong or inaccurate. 1. we recommend that you set auto-growth when creating a database to

Preparations before deploying SQL Server on the new Server When you need to deploy a new server, you may encounter many mistakes if you have no deployment experience, and make the maintenance work more difficult in the future, here I will share

Impact of InnoDB Isolation Mode on MySQL Performance I have written two articles over the past few months: one is the dangerous debt related to the history of InnoDB transactions, and the other is the truth about the serious performance problems

Redis persistence-How RDB works and Problems Working principle of Redis persistent RDB mode: Redis persistent RDB mode. Redis uses the copy on write mechanism of the fork command. When a snapshot is generated, the current process is completely

Install Oracle 11gR2 on Ubuntu 14.04 (amd64) After a week of trouble, I finally got it. Although there are many online tutorials, most of them are just a few words. In addition, the individual installation situations vary, and many places still need

Redis client 2.0.0 pipeline list rpop bug, redisrpop Description: The rpop of the list OF redis client 2.0.0 pipeline has a serious bug. When the rpop list is used, if the list is already empty, the Response from rpop is still not null, causing the

Oracle check constraints and oraclecheck ConstraintsA check constraint is a check constraint. When a check constraint is used, each input data is checked. Only records that meet the conditions are saved in the table, this ensures Data Validity and

Oracle view, oracle view Creation Oracle ViewSimple View View a virtual table that contains a series of columns and row data with names, just like a real table.However, the view does not store the actual value in the database. The database only

MySQL multi-version concurrency control analysis, mysql version concurrency When the read is not committed, the read transaction reads the master record directly, regardless of whether the update transaction is complete. READ_COMMITTEDWhen a read

[DAO] database three paradigm description, dao Database paradigm**************************************** ********************************* *** Original article: blog.csdn.net/clark_xu Xu changliang's column**************************************** ***

Detailed description of db file sequential read wait event, dbsequential Db file sequential read (this article is translated by thomaswoo_dba. For more information, see the source) The db file sequential read event has three parameters: file #,

Oracle generates an AWR report and oracle generates an awr report.  Original Works are from the blog of "Deep Blue blog". You are welcome to reprint them. Please note the following source when reprinting them. Otherwise, you will be held legally

When attaching a database to SQL Server, the following message is displayed: "version 661 cannot be enabled. Version 655 is supported ......", Sqlserver661655 When we use a database exported by someone else, sometimes We append the database exported

Oracle startup and shutdown, oracle startup and ShutdownOracle004 oracle-related program startup and shutdown: Disable: EM, ISQLPLUS --> listener --> database isqlplusctl stop, emctl stop dbconsole --> lsnrctl stop --> there are two ways: 1. dbstop 2

Flashback query, flashback The FLASHBACK Technology includes multiple aspects: flashback database, flashback drop, flashback query, and flashback table. Among them, flashbackdatabase uses the flash back log, the recycle bin used by flashback drop,

Oracle RAC rebuilding OCR, Votedisk, and racvotedisk Haha, I just mentioned the last article. I was bored and started another test. Environment:OS: redhat 5.8DB: Oracle 10.2.0.5 raw device We need to develop the habit of backing up ocr and votedisk

MongDB basic learning (5) -- projection, paging, sorting, aggregation, and mongdb Paging MongDB basic learning (5) -- projection, paging, sorting, and aggregation Basic syntax Learning The Chinese New Year is coming soon, tomorrow is a lover, and

What is HBase? HBase Classic explanation: http://www.cnblogs.com/skyme/archive/2012/07/25/2608310.html   HBase: Non-relational databases; distributed databases; HDFS-based minimum storage unit, which is a file storage. Column storage. (Relational

SqlServer export data files (figure), sqlserver export data 1. Right-click the database-> Tasks-> Generate Scripts 2. click Next. 3. Select to export the entire database and start a single data table. 4. Set to save as a file, set the