What is Data Abstraction?
475805
It is considered one of the important concepts of the OOP. Data Abstraction is to see what is needed and leave what is not. It enables designers to focus the immediate goals and don't care about the details.\n\n When you are unemployed and looking for a job you might not be wondering all the conditions of a particular job ad. But when you went an interview you broaden your view like asking the salary or working conditions, or the projects that are waiting. But nobody places all the details of the job to a newspaper advertisement. The job advertisement can be considered as an abstraction or unemployed person's point of view for finding a job might be...\n\nThere can be different implemntations of thiss concept in programming, like the "abstract" keyword in Java or C#. When you are declaring a method (a class' member function), if you put aan "abstract" keyword in front of it, you mustn't declare its body, the only thing you declare is its signature. When a class derives from the one that is containing the abstract method that deriving class must declare the body of abstract method.\n\nBy doing this, you would say ok I must have a nice method like this but I don't know the actual implementation of this method, so I'd rather leave it to you (the deriving class)...\n\nIt is also a useful tool for generalization...
146494
Data Integrity refers to the validity of data. \n\nData integrity can be compromised in a number of ways: \nHuman errors when data is entered \nErrors that occur when data is transmitted from one computer to another \nSoftware bugs or viruses \nHardware malfunctions, such as disk crashes \nNatural disasters, such as fires and floods \n\nI usually focus on Data Integrity checks when porting an application from one Database to another. For example Oracle To MySQL.
969293
http://www.databaseanswers.org/data_models/
213439
In data processing or information processing, a Data Processor or Data Processing Unit or Data Processing System is a system which processes data which has been captured and encoded in a format recognizable by the data processing system or has been created and stored by another unit of an information processing system.\n\nA data processor is a specialized component or form of an information processing (sub)system. Its chief difference is that it tends to perform a dedicated function (i.e., its program is not readily changeable). Its dedicated function is normally to perform some (intermediate) step of converting input ('raw' or unprocessed) data, or semi-processed information, in one form into a further or final form of information through a process called decoding / encoding or formatting or re-formatting or translation or data conversion before the information can be output from the data processor to a further step in the information processing system.\n\nFor the hardware data processing system, this information may be used to change the sequential states of a (hardware) machine called a computer. In all essential aspects, the hardware data processing unit is indistinguishable from a computer's central processing unit (CPU), i.e. the hardware data processing unit is just a dedicated computer. However, the hardware data processing unit is normally dedicated to the specific computer application of format translation.\n\nA software code compiler (e.g., for Fortran or Algol) is an example of a software data processing system. The software data processing system makes use of a (general purpose) computer in order to complete its functions. A software data processing system is normally a standalone unit of software, in that its output can be directed to any number of other (not necessarily as yet identified) information processing (sub)systems.
1119693
I think you might need to elucidate more on that question.\n\nPerhaps you mean how do you store multiple values in a data structure.\n\nPerhaps you mean how do you modify a "final" variable. In other languages this is called a constant. The point of this is that it cannot be changed at runtime.
32951
when you have a database, you can map, your tables with classes, so, using oql, should be a little easy to understand querys than sql
77222
You just have to know the basics of the database structre and how the data is stored. Belive me its not difficult.
490955
It's business middleware:\n\nhttp://searchsap.techtarget.com/gDefinition/0,294236,sid21_gci765096,00.html
602964
In general, an interface is a device or a system that unrelated entities use to interact.\n\nSo we treat it as a type. An interface defines methods which are never implemented. \n\nFor example, we will do a Interface of a Database. A database can SELECT, DELETE, UPDATE, and INSERT.\n\nAs you know we have many databases like MySQL, Postgres, MSSQL, Oracle, Derby, etc...\n\nNow as a designer I want to make one standard interface that has those methods unimplemented inside. Now when I want to add a driver (one of the databases) I just Implement that Interface.\n\nNow when I program... I just call that interface and Use those methods... If I want to change the Database Engine to someother engine, nothing changes cause the Database Class implements the Database Interface . THEY MUST FOLLOW THOSE Method names. If they do not... a error will return\n\nI hope you understand now!
617627
In programming, the process of combining elements to create a new entity. For example, a procedure is a type of encapsulation because it combines a series of computer instructions. Likewise, a complex data type, such as a record or class, relies on encapsulation. Object-oriented programming languages rely heavily on encapsulation to create high-level objects. Encapsulation is closely related to abstraction and information hiding.
1017090
What you are asking about is persisting data, likely on disk.  To do this, you can either create a file (text or binary, a fixed format or a flexible one like XML) or you can write to a database of some type (MS Access, SQL Anywhere, MSSQL, Oracle, MySQL, SQLLite, etc...)\n\nIf you have never done data persistence before, then likely the simplest way to get started is to look at the POSIX-standard functions for file manipulation (fopen(), fread(), fwrite(), fclose()) and simply write your data out as text.\n\nThe format for writing can be very simple:\n\n    var1 = value1\n    var2 = value2\n    ...\n\nStart with this approach.  As you determine that your data types are more complicated, experiment with more advanced formats:\n\n    var1 = (val11, val12, val13)\n\nStoring things into a database would save you the trouble of having to encode/decode the data, but it would mean having to learn database programming.  This is not a bad thing in any way, but it is more advanced than basic file I/O manipulation and file I/O is a fundamental programming skill on which you will grow.
119144
data integrity  \nRefers to the validity of data. Data integrity can be compromised in a number of ways: \nHuman errors when data is entered \nErrors that occur when data is transmitted from one computer to another \nSoftware bugs or viruses \nHardware malfunctions, such as disk crashes \nNatural disasters, such as fires and floods \n\nThere are many ways to minimize these threats to data integrity. These include: \n\nBacking up data regularly \nControlling access to data via security mechanisms \nDesigning user interfaces that prevent the input of invalid data \nUsing error detection and correction software when transmitting data  \n--x--\ndata security     \n In the computer industry, refers to techniques for ensuring that data stored in a computer cannot be read or compromised by any individuals without authorization. Most security measures involve data encryption and passwords. Data encryption is the translation of data into a form that is unintelligible without a deciphering mechanism. A password is a secret word or phrase that gives a user access to a particular program or system.
470752
Data integrity means the security and the accuracy of the data.  \n\nData redundancy means data that is useless because it is repeated unnecessarily.
898314
Here are some general data structures:\n\n- Set\n- List\n- Map\n- Tree\n- Table\n- Stack\n- Queue
143032
Centralized data processing & Decentralized data processing
585809
Yea, have fun spending money for nothing. theres not alot for Databasing itself. to be in the computer field you need overall knowledge of everything.
303999
This means there are three possible systems that control the application. A front end (top tier) that displays the graphics to the user. A middle layer (middle tier) that is acting as a broker for user requests and tapping the back end resources like a database. A final back end (bottom tier) is providing data services most likely.\n\nAn example would be the following type of application:\nweb browser <-> An HTTP server <-> A database \nSource(s):\nExperience