OracleStream created by a single instance and RAC

The day before yesterday, a similar experiment environment was set up on HPrx8640 according to the experiment steps in the related chapters of RAC and STREAM in hyperledger lerac. The experiment failed. Bytes

The day before yesterday, according to the experiment steps described in RAC and STREAM in oracle rac, a similar experiment environment was set up on HP rx8640, and the experiment failed. Bytes

The day before yesterday, according to the experiment steps described in RAC and STREAM in oracle rac, a similar experiment environment was set up on HP rx8640, and the experiment failed. Yesterday, I found an article "Learn oracle stream step by step" on the Internet. I first succeeded in setting up an experiment platform with two single instances, in the evening, I had a rough look at the official Oracle document Streams Concepts and Administration, so it was too cumbersome to continue reading it without patience and courage. Today, I had nothing to worry about. I tried to challenge the implementation of oracle stream under a single instance and RAC again. According to yesterday's ideas, I was so happy to have succeeded.

For more information, there is always only one database for a single instance or RAC. The difference is that the actual operation steps are similar. This reminds me of the oracle rac database version upgrade (from 10.2.0.1 to 10.2.0.4) I performed two upgrades. Of course, the first upgrade was successful, the second update failure is inevitable, because there is only one database, and only one upgrade is required. Here we also think of whether we participate in ORACLE factory OCP training or see Li bingyang's "Apply ORACLE", which emphasizes a confusing concept: the instance is an instance, and the database is a database, it is not good to confuse. The root cause of my mistakes is that I do not have a thorough understanding of the Database concept.

On page 41st of the ORACLE official document concepts, the following is a clear sentence:

"An oracle database server consists of an oracle database and an oracle insance. every time a database is started, a system global area (SGA) is allocated and oracle background processes are started. then combination of the background processes and memory buffers is called an oracle instance."

There are two meanings in this sentence. First, the database is composed of two parts: data files and instances. Second, the instance is only a group of memory structures consisting of memory buffers and background processes. We often operate a single database, so it is easy to confuse the concept of databases and instances. [Linux community] considers instances as databases and databases as instances, which is not the case at all.

It is relatively easy to understand this concept and try again. In fact, whether it is a single-instance database or oracle rac or multi-instance database, as long as you recognize that there is only one database, whether it is upgrading or building high availability, just follow the idea of a single node. For example, to upgrade the RAC database, the difference is that you need to modify the parameters in the parameter file, and the operation is quite simple. The basic concept is very important. This is also why the Foundation should be built first when the house is built, and the Foundation should be well built so that the House can be built. It is also true to think about technology.

Let's get back to this experiment.