Database Administrator

Two days ago, the ICBC website could not be opened, and then we saw the news, saying that the announcement of the price increase on the ICBC website was missing. It is estimated that the incident will soon be terminated. Last night, QQ suddenly fell

Redis is an open-source, network-supported, memory-based, key-Value Pair storage database written in ansi c. Its development is hosted by VMware. Redis is the most popular key-Value Pair storage database, according to the data of the monthly ranking

Database Version: 11.2.0.3 Symptom: When I started a test database today, I found that the database cannot be open. The error is as follows: ERROR at line 1:ORA-00600: internal error code, arguments: [kcratr_scan_lastbwr], [], [], [], [], [], [], [],

Automatic Memory Management type Automatic Memory Management: New Features of Oracle 11g, allowing the database to fully automatically manage memory SGA and PGA Components Automatic shared memory management: If this option is selected, SGA can be

RAC: Real Application Cluster (Real Application Cluster) is widely used. As an Oracle Database Cluster Environment, RAC has a complete set of management knowledge. Here I will demonstrate the restart process of rac. Recommended reading: Oracle 11g

10046 is a tool that anyone familiar with Oracle and SQL tuning is familiar. The 10046 and 10053 diagnostic events help us easily understand the behavior of the Oracle CBO optimizer and SQL Execution. In the case of commercial non-open-source Oracle,

After manual database creation (10.2.0.1), run the following command during EM creation: Emca-config dbcontrol db-repos create The following error occurs: ORA-06550: line 1, column 21:PLS-00302: component 'valid' must be declaredORA-06550: line 1,

1. Installation --------------------------------------------------------------------------------# Add an installation Source [Mongodb]Name = MongoDB RepositoryBase url = http://downloads-distro.mongodb.org/repo/RedHat/ OS /x86_64/Gpgcheck = 0Enabled

I. Hive join Optimization1. we try to place small tables on the left of join. We use Hive-0.90, so it is automatically converted. This means that small tables are automatically loaded into the memory and map side join is executed (with good

One of the new features of Oracle 12C, You can rename the data file online. Before Version 12c, if a data file is created and put in the wrong directory, or is originally put in asm, due to the missing plus signs, and so on, in the file system, you

System Environment: Operating System: AIX5300-08 Oracle software: Oracle 10g (64-bit) Installing Oracle 11g R2 Based on IBM AIX Add data files (bare devices) to the tablespace in AIX) AIX6.1 install Oracle 11g R2 Install Oracle 10201 on AIX AIX +

Flashback Query: queries the information of records stored in objects at a certain time point in the past, between the current time and a specified time point in the past. SQL> conn scott/OracleConnected.SQL> select

Environment: VBOX Oracle enterprise linux 5.8 _ X86_64 Oracle database 10.2.0.1.0 Oracle clusterware 10.2.0.1.0 When you re-build a RAC environment, because you do not want to create a new OCR/voting disk shared DISK, you plan to use the shared DISK

Build an MHA Environment Https://code.google.com/p/mysql-master-ha/ // Environment Introduction 1. Host deployment Manager: 10.10.54.154Master: 10.10.54.156Server Load balancer 1: 10.10.54.155 (Backup master) Server Load balancer: 10.10.54.157 2.

Suddenly I saw a saying on the Internet that the WHERE condition execution sequence of Oracle is from right to left. The reason is that when multiple 00904 characters in the WHERE condition of ORACLE are invalid, the error is returned in the order

Background: Recently, we are engaged in data migration. We have migrated data from U1 users in database A to U2 users in database B. We have used open-source kettle to work with the Data Pump. It's Okay during the test, but it's actually going

Sometimes, as the business grows, you need to re-plan the redo log. For example, if there are three groups of existing logs, one member in each group, and each member is 50 MB in size, it is obviously unreasonable for the production database. We

During RMAN backup, preview is often used to verify the recoverability of the current database, as well as the backup piece, archivelog, and whether the corresponding file exists during restoration. -------------------------------------- Split line -

Percona mysql 5.5.33 and mysql 5.6.14 performance test comparison: System: rhel 5.5,Test Tool: sysbench2-core CPU, hyper-threading, 4 logical CPUsInnodb_buffer_pool_size is set to 1 GB, and the number of connections is set to 1000.Test Time for each

After restarting the server, the user finds that a node in RAC cannot view the RAC status.An error occurred while checking the RAC status../Crs_stat-tCRS-0184: Cannot communicate with the CRS daemoBecause it cannot communicate with crs, check the