TYPES OF DATATYPES FOUND IN AN ORACLE DATABASE!

Types of Oracle Database Datatypes varchar2 this is the most common  datatype it allows you to store  alphanumeric characters. The length of varchar2 is 4000 bytes or characters. This was what set Oracle apart from other databases in prior years. While other databases had lengths up to 2000 Oracle had its character length set at 4000 Number  datatype: allows you to store an interger as well as decimal values date datatype not to be confused with the time stamp datatype stores the date value - the default way of...

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WHAT IS THE SGA IN ORACLE AND WHAT IS IN IT??

Oracle memory is called the SGA: there are different components of the SGA. Every database will have a section within the memory (SGA) referred to as the database buffer cache!  It is split up into little blocks in memory called the oracle data blocks. Each one of these blocks will be 8k in size. There is an algorithm that gets applied to the database buffer pool, it is the LRU (least recently used).. As the blocks get touched they get placed toward the LRU to get written to disk, Oracle keeps the most used in memory for easier access. Another...

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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...

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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. 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). Memory - This is called the System global Area (SGA) in Oracle. Processes - The third piece in an Oracle...

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