HOW DO YOU CREATE THE ORACLE PASSWORD FILE?

Oracle password file  is created using a utility called ORAPWD! You will also use this utility to make changes.

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WHAT ARE YOUR ONLINE REDO LOGS?

An online redo log tracks all of your changes to your tables.  In order to get started, you need a minimum of  two to get started on your online database; this redo log group is like a recorder, that records changes going on in your oracle database. However, you will end up having more than one group. You could end up with three groups or more.

Oracle  recommends that you multiplex your redo logs. When this redo log gets filled oracle does what is called a check point and then it writes to the next group.

This redo logs are used for database recovery. When the final group fills up it goes back to the first and writes to the first group (basically overwriting what was currently in the first group); but if you are in archive log mode, when the first group fills the information is copied onto Archived redo logs (the default is no archive log mode which overwrites the data).

If you have not archived the first log and your directory is full and you are running on archive log mode. Your  database will hang.


Here is a basic definition of an oracle database


An oracle database is  defined as three types of files, control files, data files and the redo logs! Any questions.

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THREE MOST IMPORTANT PARTS OF AN ORACLE DATABASE!

Before understanding the oracle database in depth, it is important to know the most important pieces in any database. This time we are discussing the oracle database.

1. Storage - Think of it this way, your data needs to be stored in a table, which belongs to a logical area called table space and  a table space gets mapped to a physical file called a data file. (which essentially uses disk storage).
2. Memory - This is called the System global Area (SGA) in Oracle.
3. Processes - The third piece in an Oracle database is the disk processes.

Datafiles store tables, indexes and rollback segments (undo segments in 9i on wards) and temporary files. 

The most important logical  view for a DBA is the dba_data_files - this has information about the datafiles.

Another file that controls the structure of your database is your datafiles. It is recommended that you have at least 3 control files on sepererate disk drives. This shows how when your database got created etc All three control files need to look exactly alike.

There is a v$ that will tell you the path of your control file and this is the v$controlfiles.

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TYPES OF DATABASE ADMINISTRATORS!

Here is breakdown structure of the various types of database administrators! Can you tell which one fits your personality?

1. Systems or Operational DBA
2. Architect
3. Applications DBA
4. Data DBA
5. Internet DBA  also a web dba!

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HOW THE DBA EVALUATES HARDWARE!

The DBA evaluates hardware resources  by checking whether or not there are enough disk drives available to install the oracle database software. 

What exactly does this mean, but first off, welcome you have just gotten hired as the new Database Administrator. Your first task as directed  in this small shop is to install the newly acquired oracle database software. What do you need to do? You are given a server and told go ahead and get started.

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WHO IS THE ORACLE DBA?

This is my first major post before delving into what exactly the Oracle DBA is required to do. Let us first simplify who an Oracle DBA is and what roles and responsibilities come with the position.

photo myfootpath

1. An database administrator (DBA) is the one who administers the Oracle database server.
2. Responsibilities may vary depending on the size of the company the Oracle DBA works for. For instance,  a small company in most cases might have just one Oracle Database Administrator who administers the database for applications and users. While in a Major company, what you would find are several people tasked as Database Administrators with different areas of specialization.

Now here is a list depicting the roles and responsibilities of the DBA

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WHAT KIND OF A DBA ARE YOU?

So earlier today I took a test on basically figuring out what kind of DBA I am and here is the result!

The scientist DBA is brilliant and sometimes shy, hates disorder, chaos and conundrums, and greatly enjoys diving into the internals of their database.

The scientist DBA tends to have a love of music and gravitates towards degrees in “pure” majors such as History, English, Math, or Physics.

Scientist DBAs usually keeps their offices neat and orderly, with everything in its proper place.   Their motto is “Prove it,” and they love to try out their database hypotheses on their test systems. 

• Attention to detail — Scientist DBAs like order in every area of their lives and their database is no exception. Every tablespace and table must stay optimized, and the scientist DBA gets visibly disturbed when a table takes too many extents or when a tablespace becomes fragmented. They miss nothing, and pride themselves on their close attention to every detail of their database.

• High professional standards — The scientist DBA believes that a database can be described with mathematical equations and every assertion about database behavior can be proven with experimentation. They sometimes require all developers to “prove” their changes in the test database, before allowing changes in production. The scientist DBA hates “rules-of-thumb” and revels in finding exceptions to any general assertion about database behavior.

• Highly reliable — Scientist DBAs spend their days in the test systems, posing hypotheses and cranking out scripts to “prove” their theories before making changes to their production system. The scientist DBA is very careful and meticulous and will always justify every database change (often with extraordinary detailed experimental evidence) before changing their production database.

• Extremely eloquent — Some, (but not all) of the scientist DBAs can be identified by their grandiloquent prose. These DBAs love to use obscure words and complex verbal syntax, and normally keep an Oxford English Dictionary (OED) close at-hand. They love puns and double entendres, and enjoy using obsolete words that have not been popular since the early 1800s.

Not bad so here is what this blog will focus on Database Adminstration and of course other Oracle tools you might find exciting; so welcome to the oracle virtual Classroom

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