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Database transaction: A transaction is a unit of program execution that accesses and possibly updates various data items.A transaction has many program segment such as read segment, write segment etc. We combine all segment as a unit and call it database transaction. A transaction require to maintain the following properties. These properties are often called the ACID properties. Given below the ACID properties of a transaction: Atomicity:   All operations of a transaction must be completed otherwise the program must aborted. Consistency: Database consistency stats that only valid data will be written to database. Database consistency says that total sum of enter program of a transaction must unchanged. If a transaction violets the database consistency rules, the entire database will be rolled back and the database restored. Isolation: Isolation means multiple transactions occurring at same time but not impact each other execution. A transaction X and another transaction Y occur at...

B tree indices are similar to B+ tree indices. The primary distinction between the two approaches is that a B-tree eliminates the redundant storage of search key values. Search keys are not repeated in B tree indices. Given below the major difference between B tree and B+ tree structure. 1.   In a B tree search keys and data stored in internal or leaf nodes. But in B+-tree data store only leaf nodes. 2.   Searching of any data in a B+ tree is very easy because all data are found in leaf nodes otherwise in a B tree data cannot found in leaf node. 3.   In B tree data may found leaf or non leaf node. Deletion of non leaf node is very complicated. Otherwise in a B+ tree data must found leaf node. So deletion is easy in leaf node.   4.   Insertion of a B tree is more complicated than B+ tree.      5.    B +tree store redundant search key but b-tree has no redundant value.     6.   In B+ tree leaf node data are ordered in a sequ...

The word database is really an important thing for large organization where needs to maintain huge users' information. If this information is sensitive in nature, the company must follow some guidelines to restrict this information from unauthorized accesses. In this dynamic world the information is increasing very high rate and company try to collect and manage this information to analyze and take perfect decision. Sometimes we use the information to make our research and get a competitive advantage from another researcher.  Multinational company's are trying to use upgraded and secured database like Oracle database, Microsoft SQL database and many more. There are huge IT populations are involved to maintain the company database. So we say that database developers need are increasing with great pace and in the near future 20% job will be available for database developers. To be an expert database developer what should you have to learn. Here is some direction that will help yo...

If we want to design and develop a database, we need to know about the database schema. A database schema is a logical design of any given database. We can divide each schema into different database tables ( all tables are same name). Database schema works like a blueprint of any database. 

Hi, how are you? In this tutorial I will clarify you the timestamp based protocol with explanation. I think this tutorial may help you to understand the timestamp based protocol easily. Now think the given picture.  This is a picture of real timestamp. Real timestamp show you the time. But database timestamp what is it? Yes, database timestamp is same as real timestamp.  What is a database timestamp? Database timestamp is nothing but it counts the time of any transaction. It builds with sequence of character which show you the time of any transaction. We use the timestamp to compare transaction duration between transaction. So we say that database timestamp is same as the real timestamp but we use these types of timestamp in different purpose. Why we use Timestamp in the database? To compare one transaction to another we use the timestamp. We count the transaction duration using timestamp . If one transaction timestamp is greater than another transaction timestamp. The pr...