In a B-tree deletion process, when a node is deleted, the tree is rebalanced by redistributing keys among sibling nodes. For example, if a key is deleted from a node with two children, the key from a sibling node can be moved to maintain balance. This process continues recursively until the tree is balanced.
A binary tree is a finite set of nodes which is either empty or consists of a root and two disjoint binary trees called the left subtree and the right subtree.We can define the data structure binary tree as follows:structure BTREEdeclare CREATE( ) --> btreeISMTBT(btree,item,btree) --> booleanMAKEBT(btree,item,btree) --> btreeLCHILD(btree) --> btreeDATA(btree) --> itemRCHILD(btree) --> btreefor all p,r in btree, d in item letISMTBT(CREATE)::=trueISMTBT(MAKEBT(p,d,r))::=falseLCHILD(MAKEBT(p,d,r))::=p; LCHILD(CREATE)::=errorDATA(MAKEBT(p,d,r))::d; DATA(CREATE)::=errorRCHILD(MAKEBT(p,d,r))::=r; RCHILD(CREATE)::=errorendend BTREE
It open at 9.00a.m all week.
They are the same thing - two different ways of writing B-Tree.
Outside of academia I do not think linked list are important, a btree is important. As for a real-world application, I do not recall one. I did use a linked list back in the days of the Apple 2/Commodore 64 but That was before hard drives (were affordable) and before I got my hands on btree source code.
You might look at the header record if the linked list has one. Better yet graduate to a btree and all these problems go away
A binary tree can be empty, or consist of three parts: a 'value' (any type), and to binary trees, called as 'left child' and 'right child'
Good question, it defies an answer because I do not have the text book that your teacher is posing questions from. Besides when you have a btree linked lists look kind of stupid.
A database is a collection of data organized in a fashion that facilitates updating, retrieving, and managing the data. The data can consist of anything, including, but not limited to names, addresses, pictures, and numbers. Databases are commonplace and are used everyday. For example, an airline reservation system might maintain a database of available flights, customers, and tickets issued. A teacher might maintain a database of student names and grades. Because computers excel at quickly and accurately manipulating, storing, and retrieving data, databases are often maintained electronically using a database management system. Database management systems are essential components of many everyday business operations. Database products like Microsoft SQL Server, Sybase Adaptive Server, IBM DB2, and Oracle serve as a foundation for accounting systems, inventory systems, medical recordkeeping sytems, airline reservation systems, and countless other important aspects of modern businesses. It is not uncommon for a database to contain millions of records requiring many gigabytes of storage. For examples, TELSTRA, an Australian telecommunications company, maintains a customer billing database with 51 billion rows (yes, billion) and 4.2 terabytes of data. In order for a database to be useful and usable, it must support the desired operations, such as retrieval and storage, quickly. Because databases cannot typically be maintained entirely in memory, b-trees are often used to index the data and to provide fast access. For example, searching an unindexed and unsorted database containing n key values will have a worst case running time of O(n); if the same data is indexed with a b-tree, the same search operation will run in O(log n). To perform a search for a single key on a set of one million keys (1,000,000), a linear search will require at most 1,000,000 comparisons. If the same data is indexed with a b-tree of minimum degree 10, 114 comparisons will be required in the worst case. Clearly, indexing large amounts of data can significantly improve search performance. Although other balanced tree structures can be used, a b-tree also optimizes costly disk accesses that are of concern when dealing with large data sets. Databases typically run in multiuser environments where many users can concurrently perform operations on the database. Unfortunately, this common scenario introduces complications. For example, imagine a database storing bank account balances. Now assume that someone attempts to withdraw $40 from an account containing $60. First, the current balance is checked to ensure sufficent funds. After funds are disbursed, the balance of the account is reduced. This approach works flawlessly until concurrent transactions are considered. Suppose that another person simultaneously attempts to withdraw $30 from the same account. At the same time the account balance is checked by the first person, the account balance is also retrieved for the second person. Since neither person is requesting more funds than are currently available, both requests are satisfied for a total of $70. After the first person's transaction, $20 should remain ($60 - $40), so the new balance is recorded as $20. Next, the account balance after the second person's transaction, $30 ($60 - $30), is recorded overwriting the $20 balance. Unfortunately, $70 have been disbursed, but the account balance has only been decreased by $30. Clearly, this behavior is undesirable, and special precautions must be taken. A b-tree suffers from similar problems in a multiuser environment. If two or more processes are manipulating the same tree, it is possible for the tree to become corrupt and result in data loss or errors. The simplest solution is to serialize access to the data structure. In other words, if another process is using the tree, all other processes must wait. Although this is feasible in many cases, it can place an unecessary and costly limit on performance because many operations actually can be performed concurrently without risk. Locking, introduced by Gray and refined by many others, provides a mechanism for controlling concurrent operations on data structures in order to prevent undesirable side effects and to ensure consistency. For a detailed discussion of this and other concurrency control mechanisms, please refer to the references below. reference http://www.bluerwhite.org/btree/