my_idea_Is

A.Discuss what have you learn and undestood what is relationship of DBMS,so far?

The DBMS is interact to the computer system to store data,is just an application that let you store the informatiojn of database and responsible to build the database,storage devices to build data structure in order you to have database.The DBMS to maintain the data structure,data,database.
The data is a representation of facts,concepts or instructions in a formalized manner suitable for communication,interpretation or processing by human beings or by automatic means.Well managed data can save time,money,increase productivity.
Database-A computer database is a program that lets you store,manage and manipulate data.

B.Define how each of the following fit and function within the framework of relational DBMS system:
1.)key fields -primary key,foreign key
2.)Database Records-holds record of the database
3.)Data Queries-allows us to store data in different ways
4.)Data types-
5.)Data forms-allows us to build a user-friendly interface for our user
6.)Tables/Database-allowa to make a table in plan our database
7.)Relationships(table linkages)-allow us to format a data in table for linkages

MY_ASSIGNMNT

A. What are data types?

A data type in a programming language is a set of data with values having predefined characteristics. Examples of data types are: integer, floating point unit number, character, string, and pointer. Usually, a limited number of such data types come built into a language. The language usually specifies the range of values for a given data type, how the values are processed by the computer, and how they are stored.With object-oriented programming, a programmer can create new data types to meet application needs. Such an exercise as known as "data abstraction" and the result is a new class of data. Such a class can draw upon the "built-in" data types such as number integers and characters. For example, a class could be created that would abstract the characteristics of a purchase order. The purchase order data type would contain the more basic data types of numbers and characters and could also include other object defined by another class. The purchase order data type would have all of the inherent services that a programming language provided to its built-in data types.Languages that leave little room for programmers to define their own data types are said to be strongly-typed languages.

B. What role do they play in a database?

Data Types -- The Easiest Part of Database DesignDatabase design can be very complicated, and it truly is an art as opposed to a science; sometimes there are multiple correct ways to model the same data with pros and cons to each. I can understand that normalization can be tricky to comprehend and to implement, and that concepts like stored procedures and foreign keys and even indexes and constraints can take time to grasp.But -- what about Data Types? They are so basic, so simple, so fundamental; not only for database design, but for any sort of programming in general ... what excuse is there for not using correct data types for the columns in a table design?I see it time and time again in the SQLTeam forums -- "dates" that don't sort properly, "numbers" that don't add correctly, "boolean" columns containing 10 different values, invalid entries that somehow show up in "date" columns, and so on ... Of course, since we are rarely provided any DDL to review, it often takes dozens of posts going back and forth until we finally realize: "wait ... you aren't using a datetime data type to store these dates??? Arggh!!"In short, even a poorly designed database, with one giant "master" table with no normalization or logic anywhere in sight, should still at least use a Money data type to store currency values!Perhaps the confusion comes from Excel users, where data types are handled behind the scenes ... or maybe "old school" VB programmers used to using variant data types (or worse -- undeclared variables!) to store values... But when you design a table in any database, you are always explicitly stating the data types of the columns -- there's nothing hidden, or no option to ignore them. You must declare a data type when creating a column, so how can anyone justify using VARCHAR to store a date?

C. Enumerate 3 data types of DBMS and explain.

1. Fixed-length textThe char data type is used to store fixed-length text with up to 255 characters. Specifying the number of characters to store limits how big the column will be. Text values retrieved from a char column are padded with spaces, if necessary, to the size of the column. The char data type is not available from the Access designer.The following statement creates a table with a 10-character text column and a 255-character text column, both with Unicode compression:CREATE TABLE T1 (c1 char(10) WITH compression, c2 char WITH compression)2. Variable-length textThe varchar data type is used to store variable-length text with up to 255 characters.Text values retrieved from a varchar column are trimmed of any trailing spaces.The following statement creates a table with a 10-character text column and a 255-character text column, both with Unicode compression:CREATE TABLE T2 (c1 varchar(10) WITH compression, c2 varchar WITH compression)3. Text BLOBThe longchar data type is used to store variable-length text with an unspecified number of characters, limited only by the maximum size of JET database files (2 GB – about 1 billion uncompressed Unicode characters).Some software libraries are able to handle longchar columns as basic text columns, but others must use BLOB techniques for accessing their data. In particular, the ADO components so often used in Visual Basic, VBA and ASP applications can access longchar columns as basic text when using the JET 4.0 OLE-DB provider to access the database, but must use BLOB handling routines (GetChunk / AppendChunk) when using an ODBC connection.The following statement creates a table with two variable-length text BLOB columns, both with Unicode compression:

MV vs. DATAF

Characteristics of Memory Variable:

* Memory variable files are a way to store the status of memory variables that are currently stored in memory and use them later in the same program or in another session of FoxPro.
The memory location holds values- perhaps numbers or text or more complicated types of data like a payroll record. Operating Systems load programs into different parts of RAM so there is no way of knowing exactly which memory location will hold a particular variable before the program is run. By giving a variable a symbolic name like "employee_payroll_id" the compiler or interpreter can always work out where to store the variable in memory.

Characteristics of Data Field:

* A data field is the smallest subdivision of the stored data that can be accessed. A data field can be used to store numerical information such as price, count or a date or time, or even a data and time. A pair of data fields can be used in combination to hold a geo-spatial coordinate. Also, a data field can be used to hold a block of text. A data field takes up permanent storage within the data-store. The field may contain data to be entered as well as data to be displayed.

ITS 121B TERM CONTRAST

A.Data vs. Information
=Data: (ISO) A representation of facts, concepts or instructions in a formalised manner suitable for communication, interpretation or processing by human beings or by automatic means.Letters, numbers, colours, symbols, shapes, temperatures, sound or other facts and figures are data suitable for processing.
Information: (ISO) The meaning that is applied to data by means of the conversions applied to that data. I.E. processed data.

Data
Raw material for computer processing for example, numbers, text, images, and sounds, in a form that is suitable for storage or processing by a computer.
• The ability to gather, store, process, and retrieve data in a timely manner is vital
• Well managed data can
– save time and money
– increase productivity
– enhance decision making

Information
Computer data that has been organized and presented in a systematic fashion to clarify the underlying meaning.

B.Computer storage vs.Data Storage

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Data storage vs. computer storage
Computer data storage
computer data storage, often called storage or memory, refers to computer components, devices, and recording media that retain digital data used for computing for some interval of time. Computer data storage provides one of the core functions of the modern computer, that of information retention. It is one of the fundamental components of all modern computers, and coupled with a central processing unit (CPU, a processor), implements the basic computer model used since the 1940s.
In contemporary usage, memory usually refers to a form of semiconductor storage known as random access memory (RAM) and sometimes other forms of fast but temporary storage. Similarly, storage today more commonly refers to mass storage - optical discs, forms of magnetic storage like hard disks, and other types slower than RAM, but of a more permanent nature. Historically, memory and storage were respectively called primary storage and secondary storage.
The contemporary distinctions are helpful, because they are also fundamental to the architecture of computers in general. The distinctions also reflect an important and significant technical difference between memory and mass storage devices, which has been blurred by the historical usage of the term storage. Nevertheless, this article uses the traditional nomenclature.
Any data storage device; that records (stores) or retrieves (reads) information (data) from any medium, including the medium itself. A data storage device is a device for recording (storing) information (data). Recording can be done using virtually any form of energy, spanning from manual muscle power in handwriting, to acoustic vibrations in phonographic recording, to electromagnetic energy modulating magnetic tape and optical discs.
A storage device may hold information, process information, or both. A device that only holds information is a recording medium. Devices that process information (data storage equipment) may either access a separate portable (removable) recording medium or a permanent component to store and retrieve information.

C.OPERATING SYSTEM VS. COMPUTER SYSTEM

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Operating system (commonly abbreviated to either OS or O/S) is an interface between hardware and user; it is responsible for the management and coordination of activities and the sharing of the resources of the computer. The operating system acts as a host for computing applications that are run on the machine. As a host, one of the purposes of an operating system is to handle the details of the operation of the hardware. This relieves application programs from having to manage these details and makes it easier to write applications. Almost all computers (including handheld computers, desktop computers, supercomputers, video game consoles) aswell as some robots, domestic appliances (dishwashers, washing machines), and portable media players use an operating system of some type. [1] Some of the oldest models may however use an embedded operating system, that may be contained on a compact disk or other data storage device.
Operating systems offer a number of services to application programs and users. Applications access these services through application programming interfaces (APIs) or system calls.

The Computer System Hardware category groups classes together that represent hardware related objects. Examples include input devices, hard disks, expansion cards, video devices, networking devices, and system power.

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Data structure except the reported one

Linked List

is one of the fundamental data structures, and can be used to implement other data structures. It consists of a sequence of nodes, each containing arbitrary data fields and one or two references ("links") pointing to the next and/or previous nodes. The principal benefit of a linked list over a conventional array is that the order of the linked items may be different from the order that the data items are stored in memory or on disk, allowing the list of items to be traversed in a different order.

How it access

If you have read books on memory then you would have come across a concept similar to linked lists. All these books usually explain one method for remembering the names of random objects in order. For example, your friend might read out the following list to you just once:
Sheep, carpet, bottle, cigar, tent
and throw a challenge. The challenge is that after a few minutes you should be able to recollect the five names in the same order. Not a big deal, right? Try it with 20 and you’ll realize the difficulty. Memory experts suggest that we associate each object with the next one in the list; or in other words create a link between every neighbouring object. In our case we might say, “A sheep was born on a carpet, the carpet was rolled into a bottle, the bottle smoked a cigar, the cigar was resting in a tent!” The idea is to form comical associations between two objects since these associations are retained in our memory longer. The beauty of this technique is that if your friend names any object from the list, you will be able to say what is the next object in the list (irrespective of the object’s position in the list).

Actual structuring

To aid in the understanding of the linked list concept, let's write a little program which will simulate a linked list. The program should do the following:
Store a set of integers.
It should be possible to delete a particular element.
Permit insertion of a new node (element).
Deletion of a particular node.
A way to display the entire contents of the list.
Let's do this program the OOPs way. First of all we need to have an idea about how we are going to represent a single node of the linked list. The simplest way is to use a structure for a node.

struct node
{
int data;
node *next;
};
'data' is used to hold the data. In this case we are creating a linked list to store only integers (so 'data' is of type int). Every node contains a pointer to the next node. For this we create a pointer pointing to an object of type 'node'. Thus the pointer 'next' will contain the address of the next node.


How is data kept

A data structure is simply a way of organizing data and we have organized data in our shopping list as well. From what we’ve learnt so far we would categorize this as an array perhaps. The information isn’t sorted and we simply keep increasing the list when we think of more things to buy. But the problem with arrays is that they are fixed. You can’t keep on increasing their size as and when you feel like it. So we have a better data structure called a vector to serve this purpose.

"Defined ITS 116"

Kind of Data structure

Definition of Stack

• A stack is a data structure that allows items to be added and removed from one end. That's why it's also described as a LIFO stack. Last In First Out. A stack can be directly compared to some real-life objects. For example, a stack of trays. Trays are only added and removed from the top. A stack of exercise books can also be used as another analogy. Students only take away or pass up exercise books from the top.

Definition of Dictionary

• An abstract data type storing items, or values. A value is accessed by an associated key. Basic operations are new, insert, find and delete.
  Formal Definition: The operations new(), insert(k, v, D), and find(k, D) may be defined with axiomatic semantics as follows.
  new() returns a dictionary
  find(k, insert(k, v, D)) = v
  find(k, insert(j, v, D)) = find(k, D) if k ≠ j

where k and j are keys, v is a value, and D is a dictionary.

Definition of Bag

• An unordered collection of values that may have duplicates.
  Formal Definition: A bag has a single query function, numberIn(v, B), which tells how many copies of an element are in the bag, and two modifier functions, add(v, B) and remove(v, B). These may be defined with axiomatic semantics as follows.
  new() returns a bag
  numberIn(v, new()) = 0
  numberIn(v, add(v, B)) = 1 + numberIn(v, B)
  numberIn(v, add(u, B)) = numberIn(v, B) if v ≠ u
  remove(v, new()) = new()
  remove(v, add(v, B)) = B
  remove(v, add(u, B)) = add(u, remove(v, B)) if v ≠ u
• where B is a bag and u and v are elements.

Definition of Set

• An unordered collection of values where each value occurs at most once. A group of elements with three properties: (1) all elements belong to a universe, (2) either each element is a member of the set or it is not, and (3) the elements are unordered.
  Formal Definition: As an abstract data type, a set has a single query function, isIn(v, S), which tells whether an element is a member of the set or not, and two modifier functions, add(v, S) and remove(v, S). These may be defined with axiomatic semantics as follows.
  new() returns a set
  isIn(v, new()) = false
  isIn(v, add(v, S)) = true
  isIn(v, add(u, S)) = isIn(v , S) if v ≠ u
  remove(v, new()) = new()
  remove(v, add(v, S)) = remove(v, S)
  remove(v, add(u, S)) = add(u, remove(v, S)) if v ≠ u
• where S is a set and u and v are elements.

Definition of Graph

• In computer science, a graph is a kind of data structure, specifically an abstract data type (ADT), that consists of a set of nodes (also called vertices) and a set of edges that establish relationships (connections) between the nodes. The graph ADT follows directly from the graph concept from mathematics.
  Informally, G=(V,E) consists of vertices, the elements of V, which are connected by edges, the elements of E. Formally, a graph, G, is defined as an ordered pair, G=(V,E), where V is a set (usually finite) and E is a set consisting of two element subsets of V.

Definition of Buffer

• In computing, a buffer is a region of memory used to temporarily hold data while it is being moved from one place to another. Typically, the data is stored in a buffer as it is retrieved from an input device (such as a keyboard) or just before it is sent to an output device (such as a printer). However, a buffer may be used when moving data between processes within a computer. This is comparable to buffers in telecommunication. Buffers can be implemented in either hardware or software, but the vast majority of buffers are implemented in software. Buffers are typically used when there is a difference between the rate at which data is received and the rate at which it can be processed, or in the case that these rates are variable, for example in a printer spooler.

Definition of Hash Table

• In computer science, a hash table, or a hash map, is a data structure that associates keys with values.
• The primary operation that hash functions support efficiently is a lookup: given a key (e.g., a person's name), find the corresponding value (e.g., that person's telephone number). It works by transforming the key using a hash function into a hash, a number that is used as an index in an array to locate the desired location ("bucket") where the values should be.
  In most cases the hash function is deliberately chosen to have pseudo-random properties, so that small changes of key gives a large and apparently random effect (although of course reproducible effect) on the hash returned. Because of this random effect in some cases the calculated index can be the same for two different keys (a "collision"); different hash table designs handle this issue in different ways.

Definition of Skip List

• A skip list is a probabilistic data structure, based on multiple parallel, sorted linked lists, with efficiency comparable to a binary search tree (order log n average time for most operations).
  Underlying the skip list is an augmentation of an ordered linked list with additional forward links, added in a randomized way with a geometric/negative binomial distribution [1], so that a search in the list may quickly skip parts of the list (hence the name). Insert, search and delete operations are performed in logarithmic randomized time.

Definition of Bitboard

• A bitboard, often used for boardgames such as chess, checkers and othello, is a specialization of the bitset data structure, where each bit represents a game position or state, designed for optimization of speed and/or memory or disk use in mass calculations. Bits in the same bitboard relate to each other in the rules of the game often forming a game position when taken together. Other bitboards are commonly used as masks to transform or answer queries about positions. The "game" may be any game-like system where information is tightly packed in a structured form with "rules" affecting how the individual units or pieces relate.

Definition of Priority Queue

A priority queue is an abstract data type in computer programming that supports the following three operations:

• InsertWithPriority: add an element to the queue with an associated priority
• GetNext: remove the element from the queue that has the highest priority, and return it (also known as "PopElement(Off)", or "GetMinimum")
  PeekAtNext (optional): look at the element with highest priority without removing it

"Array"

An array is a series of elements of the same type placed in contiguous memory locations that can be individually referenced by adding an index to a unique identifier. That means that, for example, we can store 5 values of type int in an array without having to declare 5 different variables, each one with a different identifier. Instead of that, using an array we can store 5 different values of the same type, int for example, with a unique identifier.


For example, an array to contain 5 integer values of type int called billy could be represented like this:
0 1 2 3 4
billy ____
int

where each blank panel represents an element of the array, that in this case are integer values of type int. These elements are numbered from 0 to 4 since in arrays the first index is always 0, independently of its length.

First index (0)

0 1 2 3 4 5 6 7 8 9 -----indices

billy ____ __ Element (at indexes 8)

---------------Array length is 10-------------------

Array dimensions:

In the most of cases the Array has one dimension like the description above, but in some case the Array has more than one dimension (In MQL4 the maximum dimension is four dimensions).Multi-dimensional arrays are very like multi-column tables, where the first column is the first dimension of the Array and the second column is the second dimension of the Array etc.

Creating an Array:

The arrays must to be declared (like the variables) before using it in the code. Declaring an array means creating it by giving it a name (identifier), type and size. In MQL4 we are creating the Arrays like this:int myarray[50];

In the code above we declared one-dimensional array.int keyword indicates that the array is an array of integers.myarray is the name of the array (identifier).[] telling the compiler that we are declaring an array not an integer variable.50 is the size of the array.

We have now a one-dimensional array of 50 integersdouble myarray[5][40];

The line above is the way to declare two-dimensional of seven arrays each of them consisting of 40 doubles.Initializing the Array:Initializing an array (or a variable) means setting its value at the same declaration line.Look at this code which initializes one- dimensional array of 6 integers:

int myarray [6] = {1,4,9,16,25,36};

Example arrays
1-D: [ 3. 1. 4. 1.]
2-D:
[[1 2 3]
[4 5 6]]

3-D:
[[[ 1 2]
[ 3 4]
[ 5 6]]
[[ 7 8]
[ 9 10]
[11 12]]]