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After carefully studying the GoldenGate enterprise-level O & M practices, I focused on my understanding of several OGG processes. Combined with my understanding of the principles, I tried the experiment for nearly two days and configured it four

Introduction to ORACLE Data Analysis and Dynamic Sampling: the most important thing to pay attention to when optimizing oracle database performance is SQL Execution efficiency, the most intuitive tool for reflecting SQL efficiency is the execution

I think timesten is a bit more powerful. You can directly load the entire table to the timesten cache database through ttisql. The following is an example. 1. Create a table "test" in oracle ". I think timesten is a bit more powerful. You can

I created a storage process for sending emails a few days ago. I wanted to automatically send the daily running status of the database to my mailbox. I didn't expect a problem the next day. A large number of xxx_j000_xxx.trc files were generated in

We all know that MySQL master-slave replication is transmitted in plain text, which is not allowed for some special businesses. Next we will try to build an SSL-based master-slave replication environment: RHEL5.8SELinux disabled, iptables disabled,

1. modify Database Name 1. View oracle Instance name 2. shutdownimmediate3.lsnrctlstop $ ORACLE_SID # ---------- disable oracle service in windows 4. Modify etcoratab's $ ORACLE_SID #------ 1. modify Database Name 1. View oracle Instance name 2.

Introduction: Latch contention is caused by multiple sessions accessing the same data block at the same time. This is what we often call Hot blocks. Solution: scatter records into multiple data blocks to reduce frequent accesses to multiple sessions

Environment: Centos6.3 and mysql5.1Centos6.3. After installing mysqlclient and server, garbled code appears and you have to modify the encoding. Note: For details about the differences between utf8 and gbk, refer to: How to Solve linux Chinese

I saw some people discussing the difference between pre-read and physical read on the internet today. I personally think that both physical read and pre-read operations require reading data from the disk to the memory, the reading time is different,

When I create a USER in the new database today, I need to configure resource restrictions. I haven't been playing ORACLE for a long time, and I have been playing this thing almost. Userprofile includes two parts: 1. resource restrictions, When I

In the database, there is a data table Student with the fields StudentID, StudentName, and ClassID. StudentID is not a continuous number. The current task is to query data within the specified range, for example, you want to query the fifth and

Fields basically share the same meaning as columns, which are often used in exchange. However, database columns are generally called columns, while term fields are usually used together with calculated fields. Concatenate concatenates values

This article mainly organizes Forum content. (Forum address: bbs. et8.netbbsshowthread. php? T1026112) Many people have encountered RAID 5 failure on the server. Usually, after a disk is dropped, the second disk is immediately dropped. This article

Fault Phenomenon: [oracle @ L-DB-100-17 ~] $ SqlplusassysdbaSQL * Plus: Release10.2.0.4.0-Productionon Saturday January 5: 152002 Copyright (c) 1982,2007, Oracle. AllRightsRes Fault Phenomenon: [oracle @ L-DB-100-17 ~] $ Sqlplus/assysdbaSQL * Plus:

1. What is a rollback segment? 1. rollback segment table space. The official name of Oracle is "Restore table space": You can restore multiple tablespaces. However, at any time, only one tablespace can be restored .. 1. What is a rollback segment? 1.

In MySQL5.1.X, create and delete clustered indexes: 1. Create an empty table with the same structure as the original table, and then create a clustered index. 2. copy the data from the original table to the new table, an exclusive lock will be

The LOB page in SQLSERVER is a simple study. This article is complementary to my other article, before reading the article "Simple Research and Test of SQLSERVER2012 column storage Index", I hope you can read this article o (_) first (_) I believe

I. Transaction criterion (ACID) 1. Atomic execution: either done or not done; 2. Functional Consistency ): DBMS data should be consistent from one State to another; 3. Data Isolation between each other (Isolation): multiple transactions can be

In earlier versions, if a high-load machine is restarted and a large amount of hot data in the memory is cleared, it will re-load the data from the disk to the Buffer_Pool buffer pool, in this way, the performance will become very poor during peak

1. Shared resources of a queue can be accessed by multiple sessions and processes at the same time. Therefore, access to these resources must be protected. In Oracle, apart from PGA, everything (including memory, disk, CPU, table, index, transaction,