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Structured Query Language


SQL is language of query standard for the DBMS. SQL taken as standard since year 1992. Initially applied at big DBMS like Oracle and of Informix, by now at DBMS base on PC like and dBASE of Foxpro. SQL have the character of as high level language. User only mentioning result of which is wanted and optimize execution of query conducted by DBMS. Language of SQL divided in two big shares, that is : DDL (Data of Definition Language) and DML (Data of Manipulation Language). DDL define data bases structure, like making of data bases, making of its tables. Example : CREATE DATABASE and of CREATE TABLE. DML represent shares for the manipulation of data bases like : data access, abolition, addition and distorting of data. DML also can be used to conduct data computing. Example : INSERT, DELETE, and UPDATE. SQL is relied on operations gathering of relational which have modify and repair.

Elementary structure of SQL consist of three clause, that is SELECT, FROM, and WHERE. SELECT have correspondence to with operation of projection at algebra relational. SELECT used to present attribute list at result of query. FROM have correspondence to with operation of Cartesian product at algebra relational. FROM used as by list an relationship table to process and in evaluation. WHERE have correspondence to with operation of selection at algebra relational. WHERE consist of predicate covering attribute in relationship which emerge at clause of FROM. Clause of WHERE used to determine criterion or predicate which must in fulfilling an relationship as result of query. This clause have the character of optionally, that is can use clause of WHERE or do not. Otherwise use clause of WHERE, hence query conducted by for all tuples at tables of which is mentioned at clause of FROM. Predicate at clause of WHERE can be combined with other relationship operator, like <, <=, >, >=, <> and logic operator, like AND, OR, NOT. Clause of WHERE can be used to conduct query with predicate which in form of an certain value range, that is by enhancing clause of BETWEEN. For attribute which is have type to of string can be conducted by an seeking with certain pattern, that is by exploiting character ‘%’ or ‘_’ (underscore) and enhance clause of LIKE at clause of WHERE ‘%’ for all substring ‘_’ for all appropriate character on course. Clause FROM used to determine tables to be made as source for the seeking of data In conducting query do not only limited to one tables, but is frequently required for relationship some tables at the same time. To present result of query pursuant to certain attribute sequence, hence can be conducted by enhancing clause ORDER BY, given by default is clause ORDER BY is sequence by menial (ASC), but to change to become sequence by is downhill, can be conducted by enhancing clause of DESC after name of attribute.
Functions of aggregation SQL :
• AVG : to get average value an attribute which is have type numeric.
• MIN : to get smallest value an attribute which is have type numeric.
• MAX : to get biggest value an attribute which is have type numeric.
• SUM : to get total value an attribute which is have type numeric.
• COUNT : to get value to the number of tuples.
Value NULL at one particular query can be treated peculiarly, that is earning is also treated for query to use expression of SQL. Manipulation data operations consist of addition of new tuple, distorting of attribute value, and abolition of tuple at one particular tables.
Command of SQL for the definition of data :
• CREATE : to form data bases, index or table.
• ALTER : to alter structure of table.
• DROP : to vanish data bases, index or table.
For the domain of data type cover as follows :
• Char(n) : type of String with length remain to equal to character n (if filled in character length less than n, hence the rest in content with space).
• Varchar(n) : type of String with flexible length, but maximal counted character n.
• Integer or int : integer type 2 byte.
• Smallint : type Integer 1 byte.
• Real, double, precision : type fraction of point floating decimal.
• Float(n) : type fraction of point floating decimal with digit n precision.
• Date : Type of is date of (composing 4 year digit of month, moon, and date).
• Time : time type (consisted of hour, minute, and second).
If an tables have index compositely (alliance), hence conducted by writing down all attribute at clause PRIMARY KEY.

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Relational Model


Is proposed by Codd in the year 1970, that Moment model is network and hierarchy. In this time model relational become elementary and dominant data model at pledge product of SMBD. Used wide of by various vendor like Informix, Oracle, Sybase, Access, SQL Server, FoxBase, Paradox. Database represent corps from one or more relationship. Each relationship represent the tables of which consist of column and line. Its advantage in comparison with model previous data is its data representation modestly and is easy to expressed in the form of query.
Especial construction of data representation in model of relational is relationship. Relationship consist of relationship scheme and example relationship. Relationship scheme representation lead column / field of tables. Example of relationship is tables. Scheme Relationship : determining the name of relationship, name of the each field (column / attribute) and domain from each field. Domain which is mould have the name of appropriate value corps and domain. Relationship scheme determine domain to every field. Domain at every field basically is type of field. Relationship by using SQL. SQL use word of is tables of to express relationship. Condition of which is specified at database scheme of relational and limit data able to be kept in database example of relational. Kinds of definition integrity :
• Definition Key
• Definition Lock Guest
• Definition Public
Query represent question concerning data while its answer consist of new relationship which load result. Language of query represent special language which used to write down query. SQL represent language of query commercial which most popular for the SMBD of relational. Model of ER very according to depict database design early owning high level. Conducted by of approach to yield database scheme of relational which is very come near ER design.

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Design Database


Process Of Design Database

  • Analysis Conditions

Comprehending and knowing data which must be kept in database, application what have to be woke up by above him, type operate for what will be used.

  • Conceptual Design Database

Collected information at phase analyze conditions used to develop high level data description.

  • Design Data Base Logic

Change scheme of E-R become database scheme of relational.

  • Repair Of Scheme

Analysis a group of relationship in database scheme of relational to identify problems which emerge and repairing it.

  • Design Data Base Physical

This step include making of index at some tables, grouping some tables or entangle design repeat which is substantial to database scheme some part.

  • Design Application and Security

All project of software entangling a DBMS have to consider application aspect which beyond database.



Type Attribute Of E-R Diagram

  • Simple attribute that is attribute which do not be elaborated to become attribute sub, or cannot be elaborated to become other attribute.
  • Composite attribute is attribute able to be elaborated to become some attribute sub.
  • Monovalent attribute addressed at attribute having at most one value to every data line.
  • Valuable attribute many is attribute able to contain more than one value, but having same type.
  • Value of Null used by when an entity don't have an value to an attribute. Null also designate that an attribute value there no or unknown.
  • Generation attribute is attribute which is its value is obtained from processing or can be degraded by other related tables or attribute.

Kind Of Key

  • Super Key : representing an gathering which consist of one or more attribute able to differentiate every data line uniquely in a tables.
  • Candidate Key : representing minimum attribute gathering able to differentiate every data line uniquely in a tables.
  • Primary Key : representing most unique key, briefer, a more regular made by reference. Primary Key can be selected from one of candidate key.

Step Making E-R Diagram

  • Identifying and specifying all gathering of entity to involve.
  • Determining attributes of key from each gathering of entity.
  • Identifying and specifying all relationship gathering among gathering of entity existing along with foreign key.
  • Determining degree of cardinalities to every relationship gathering.
  • Equipping gathering of entity relationship gathering and with attribute of descriptive (non key).

Gathering of entity which do not have attribute able to function as primary key. Gathering of entity weak contain entity which is its apparition depend on its existence in a relationship to other entity (strong entity).



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Conduct Examination And Make Report Result Of Examination Of Program


After comprehending elementary concept of and algorithm of programming, comprehending data structure, comprehending language programming of Delphi, can develop good application program of bases and calculation data at this items will study the problem of how to test a program and make its report. Examination a application program which have been woke up to become analyst duty in giving duty to Programmer, will but as programmer have to know also how mechanism examination of program do have succeeded or not yet. Examination of program can be conducted by per shares or entirety. Examination of program per shares can be conducted by at moment making of code, while examination as a whole conducted by after all shares finish.


Examination Program

In conducting program code, a programmer have to know problems faced and know also how its. Solving of the problem of program code usually implementation in algorithm depicted with diagram emit a stream of. Diagram emit a stream of solution a problems have to convert in language of programming so that yield a computer application program according to with problems faced. Examination process a application program that is by checking off functions which have been made with various input action or input expressing from problems.


Making Report

To give report to taskmaster in this case is analyst program, needed by report result of examination of program which have been made. Report format result of examination of program can be made by mentioning examinee indicator what have is matching with the one which wanted or not yet.


Examination of woke up program represent duty from a analyst or giving duty to programmer, will but a programmer have to know the way of examination of program. Steps in doing examination of program is the following :

  • Running program

  • Giving input as according to given criterion

  • Commanding program to process input

  • Checking result of processing of program

  • Comparing result of processing of program with processing of manual

  • Giving input any

  • Paying attention what conducted by program

  • Note each result which have been got

  • Check do program which have been made have is matching with the one which expected.

  • If there is still not according with accepted, repair of program code.


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Making Application Program Bases Data With Delphi 7


Databases
Databases represent data aggregate (table) which each other is interconnected which kept in electronic storage media (disk floppy, hard disk, CD, DVD, Flash Disk, PCMCIA) so that can be added, to be edited, to be kept and accessed easily and quickly. Each organization both for having the character of profit (company, hotel, house ill, shop self-service) and also is organizational is non profit (institution governmental, organization of region, school) requiring management of easy data and quickly. Management of data manually with bookkeeping of paper assumed to have many weakness especially if amount of data have very big so that needed by system development of management with data bases.

System Organizer Of Database
Management of data bases do not be conducted directly by user but by a special application program to managing data bases of is so-called with term (Database Management System) what more knowledgeable with DBMS. Functioning DBMS to conduct organized of data where data will be kept, to be edited, to be vanished and enhanced is and also accessed by user. DBMS also function to arrange usage with data which is there are in data bases system and protect data from accessing one who have no business. In data bases management at one particular computer needed an program (software application) capable to process bases data. There is many software able to be used to manage data bases, among others is :
Base on DOS : dBase, fox base, Fox Pros and others.
Base on Windows : MS Access, Visual of Fox base, Oracle, Microsoft SQL Server, Mysql, Interbase and others.
Base on Linux : Mysql, Postgrest and others.
Initially to develop data bases program used language of programming by using data type such as those which explained by above that is can in the form of record. In this way programmer can make specific data bases file type so that do not standard. If happened change of requirement of program, hence program code have to be altered and need time old ones to make a change which in fact relative easy to. However language of programming now have provided better data bases facility that is in the form of support to data bases software which have there is so that data bases program can be woke up according to requirement.
Delphi 7 providing component of BDE, Data of Access, Data Control to connect program with data bases with program of Delphi 7. To make, to editing and vanishing databases (tables), Delphi provide Database facility of Desktop which supporting various data bases format like Paradox, dBase, Sybase Interbase, MS Acces etc.

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Drawing Up Code Program


After algorithm compiled better and correctness, hence step hereinafter is to chosen language of programming to be used to make application program. These days expanding many language of programming both for being based on text (Pascal, Basic, C, Fortran, Prologue, Cobol) and also base on graph (Borland Delphi, Visual C, C Developer) and others.


Delphi 7 representing language of programming high level very popular because mainstay, amenity, support and speed what is wide of to make application program both for modestly complex until. Idiosyncrasy of language of programming this among others that is as follows :

  • Ambulatory at Operating System of Microsoft Windows 9x, ME, 2000 and XP
  • Can be used to make calculation application program, media multi, program of interactive, data bases program and also program owning complex intelligence (complicated)
  • Easy to in its use because Delphi work by menu of user friendly
  • Delphi 7 representing language of programming visual base on mode graph so that to make program with appearance which drawing do not need long program code
  • Support programming orientation of object

component of Delphi :

1. component of pallet standard

component of pallet standard contain 16 component that is : Lable, Edit, Memo, Button, Checkbox, Radio button and others

2. component of pallet additional

component of pallet additional contain 26 component that is : Bitbtn, Speedbutton, Maskedit, Stringgrid, Image, Shape and others

3. component of pallet win32

component of palet additional contain 20 component that is : Tabcontrol, Pagecontrol, Richedit, Progressbar, Updown, Animate and others

4. component of pallet system

component of palet additional contain 20 component that is : Tabcontrol, Pagecontrol, Richedit, Progressbar, Updown, Animate and others

5. component of pallet data of access

component of pallet additional contain 6 component that is : Datasource and others

6. component of pallet data of control

component of pallet additional contain 15 component that is : DBGRID, DBEDIT, DBTEXT and others

7. component of pallet BDE

component of pallet additional contain 8 component that is : Table, SQL, Storeproc and others

8. component of pallet ADO

component of pallet additional contain 20 component that is : ADOCONNECTION, ADOTABLE, ADOQUERY and others.

Appearance menu programming of Delphi 7 consisting of Form as place to design appearance, Component as resource to be used in program, Object of Inspector as place to arrange component properties and of Code Editor as place to conduct writing of program code. Language programming of Delphi represent language of programming visual consisting of many component which is put down in component of pallet.


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Comprehending Procedure Code Program


Algorithm

Before making an program with language programming certain require to be made by program code procedure which is recognized by the name of algorithm. Algorithm represent the steps solving of a[n problem of which is compiled systematically and is logical. In fact algorithm do not only used in making of just computer application program, but also used many in everyday life. Algorithm earn analogy with procedure operating standard (SOP). In general, side doing process referred as by processor. Processor can in the form of human being, computer, other electronic appliance or robot. Processor conduct an process by executing or "executing" algorithm which formulate the process. Executing algorithm mean to do steps in Algorithm. Processor do process as according to passed to algorithm him.


Application Algorithm In Programming

Computer only one of the processor. So that can be executed by computer, algorithm have to be written in language notation of programming is so that named by program. Become program is technical implementation of written in algorithm is language of programming certain so that can be executed by computer. Learn program unlike learning language of programming. Learn program is going wise to troubleshooting methodologies and strategy, later pouring it in an easy to read certain notation and comprehended. Learn program have the character of the understanding of problem, and analysis of synthesis which is pointed at scheme of program. Learn language of programming mean to learn to wear an structure roles, instructions, operation procedures compiler, and exploit the instructions to make written program only in that just language which is pointed at program code or as coder.

Structure Data

To conduct program code have to know by data what involving or will wear in program. Data have to be defined better and real correct so that made program function better. Election of less precise data type will cause program walk unfavorable or even experience of failure of alias do not function such as those which wanted. In programming of data kept in the form of variable representing data which is its value can fluctuate. Variable value depend on included input. In programming of declaration variable structure have to with data type matching with data to be used. For example data of[is Name of student earn declaration with data type of string. Long data of pallet a trilateral earn declaration with data type or integer of real.


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Operation Structure Data Array 1 Dimension


During the time we are only studying single data structure of its meaning of data input to be processed by output data and program as result of program process have the character of single (do not team). Though problems met by in field many data type which actually is identified precisely if kept with changer (variable) with data structure of array. Array is corps data which of a kind with the each its member element owning a number of index unique element.



Seeking Of Data (Searching)

Searching an or data of searching at a group of data which of a kind is an process which is often met by field. Principal of activity of method of searching this shall be as follows : comparing to start from data (first index) till data (last index) at changer of the array with searched data, is same if some mean process seeking of success or meet, but if until is same to last data nothing that mean seeking process fail or do not be found by such data.

Sequence Data (Sorting)

Other Process which do not less important and is often met by field is process sort data in an variable of array (in this case array 1 dimension). Data sequence there is two kinds of namely massage to go up (massage and ascending) go down (descending). In massage go up, data in array will be arranged to repeat with element which is its smallest value will be placed on course number of index first and element with biggest value will be placed on course number of index last. Principle of method at massage go down / descending : started from first data (element of array at number of index first) of array 1 dimension above as directive, compared to last of data both (element of array at number of index second), if data both first data, hence both the data commuted for so that both data becoming first data and first data become both data, hereinafter compared to first data again with third data (element of array at number of index third), if third data first data hence both commuted for, that way further till last data (element of array at number of index last) compared to of first data. Comparison continued with both data as its directive, and compared to third data and so on till last data. That way recurring algorithm continue till data of n – 1 (where n is the amount of element of array entirely).

Array is data structure which consist of a group of data which of a kind. Array there is which is 1 dimension and 2 dimension. One of the method of sorting easy for implementation is method of bubble sort modified.



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Algorithm And Diagram Emit A Stream Of For The Process Of Repetition




Loop is term without ceremony to express all structure type conduct natural of repetition (iteration) that is, every structure causing program repeatedly execute an block code. Wearing loop is one of the aspect of programming which most complex in language with certain order. Knowing way of and when each that loop is wearied by very is determining of making high software with quality.


Kinds of loop is also differentiated by location where examination that perfection is executed. Examination can be executed by in early, final or middle of loop. This characteristic advise that do at least that loop is executed once. If examination conducted by in early, hence bodywork of loop needn't execute. If loop tested by in is final, organ of loop have to execute at least one times. If loop tested in the middle of, hence part of loop preceding part of examinee, executed at least once. But part of loop after, that is catching up shares which have been tested needn't execute is at all.

Loop which commonly use pursuant to its examination situation there is three kinds of: loop with examination in early, in final and in the middle. Of vital importance in order to be known the way of and when an type of loop that is wearied, because this is matter very is determining of making of software what is high with quality.


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Trouble Shooting TCP / IP


Taking example computer of Linux you is him must be continued to network, but why do not walked. How to look for wrong soybean cake of him, at the same time correct ?

First, please conceive that if you send package of network, medley the way shall be as follows :

  • Application

  • Protocol TCP / IP

  • Driver Kernel

  • Card Network

  • Cable of Network

  • Other Computer (Gateway)

  • Internet




In a word, algorithm of trouble shooting is :

  • TEST of DEVICE. If correctness hop to TEST of TCP / IP. If wrong SET last DEVICE try again. If still wrong also, check CARD and of DRIVER kernel of Linux your

  • TEST of TCP / IP. If correctness hop to TEST of PING, if wrong to SETTING TCP / last IP try again

  • TEST PING-GATEWAY. If correctness hop to TEST of PING, if wrong CHECK CABLE

  • TEST PING-INTERNET. If correctness yes have, finished. If is wrong, set last routing try again. Extension of Internet your surely is breaking




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Concept Algorithm And Diagram A Stream Of Emit


In course of software engineering can wear by some approach model. One of the model engineer software which is oldest (conventional) and have popular is model of sequential linear which is often referred as with “classic life cycle” or “waterfall model”. Earliest phase at process of software engineering with approach of model this linear sequential is analysis step. Efficacy at phase third of code (implementation) very determined by efficacy at step analyze and design. In conducted analysis phase among others is to conduct requirement survey for example : identifying and determining requirement of data. Last at phase of design conducted by remodeling of data stream steps and or program stream, till including determination of data type, data structure, input interface of output and determination of language programming wearied. For the scope of simple work of step analyze and design this can be conducted with approach of algorithm of programming and diagram emit a stream of data (program).



Algorithm Concept

Algorithm in public context is an step medley written in work is notation of descriptive logical for attainment an solution or to go to an specific purpose. Meanwhile the so called with program in general, is instruction corps or compiled command in such a manner so that have correct natural existence sequence to finish an problem. Become algorithm of programming can be explained as instruction medley or compiled command in such a manner so that have correct natural existence sequence and have to obey to finishing an problem.


Diagram A Stream Of Emit (Flow Chart)

Meanwhile to conception about diagram emit a stream of, much the same to with algorithm concept, just only here its writing more made moderate namely do not descriptive with sentences long but by wearing function symbols and operator. As for symbols which is often used in depiction of diagram emit a stream of shall be as follows.



There are some used operator namely operator of arithmetic and relationship operator (gathering). Diagram emit a stream of can represent representation of data stream or program stream (instruction medley). But usually an diagram picture emit a stream of to represent its his representation, its meaning an diagram emit a stream of can be viewed as by diagram data stream at the same time as instructions flow chart program. An diagram emit a stream of which is instruction stream representation data and program hence can be made as model or design of your software (program).


Process Ramification

Algorithm and diagram emit a stream of which have been studied by above is to using successive data structure, its meaning from first step up to last step there no ramification process (decision making), choice and or repetition. Meanwhile for the process of ramification, used if in its process, program stream medley obliged to jump or go to an certain step which is not successive, this matter often is also referred as with ramification. Process this ramification can on condition that (conditional ramification) and or do not (ramification is not conditional).


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Conducting Scheme Of Gathering Data


Stack

One of the concept which is very good for in computer science is one data structure form of is so-called heap (stack). Simply, heap can be interpreted as a corps data which impressing there is put down data above data which is other. One matter which important to remember that in stack can add and take pass back part is same, so-called as tip of heap (of top stack). Stack represent an list having the nature of “entering is last of first exit (out first in last – LIFO).



Queue

Queue represent one data structure type which is often used for the simulation of situation of real world. Queue is an data aggregate of is which addition of element only can be conducted at one particular back part (referred as with side behind or rear), and abolition (intake of element) to pass other back part (referred as with next side or front). Used term if someone enter in a queue is Enqueue. While term which is often wearied by if someone go out from queue is Dequeue. Heap use principle “enter lastly of first exit” or LIFO (Last In First Out), hence at principal queue the used is“ entering is first of exit first” or FIFO (First In First Out). Equally, sequence element exit will is equal to sequence entry.


Tree

Tree is linear data structure form do not having nature and special marking. This structure is usually used to depicting relation having the character of hierarchical between element existing. Simplest example of which we can see in everyday life, specially in family is family ancestry. Tree like picture under referred as with linear of chart where every element can have more than two branch. Simply tree can be defined as element corps which one of the its element is referred as with root and remains other element (so called node) broken to become a number of becoming gathering which each other do not correlate one another, so-called with sub tree, or is also referred as with branch. If us see in each sub tree, hence this is sub tree also have root and its it him each. Besides level, is also recognized by term degree of degree from an node. Degree of an node expressed as to the number of child or born of node. Leaf also is often referred as with external node external of node. So that other node, except root, also is often referred as with node in is internal of node. High deepness or height (depth) from an tree is maximum level of node in the tree lessened by 1. Ancestor an node is all located node in one band with the node of root until node evaluated. Forest is corps a number of tree which do not each other correlating.


Graph

Graph can be conceived as corps of object activity or, for example, town bus route from one terminal to other terminal, route journey of post package at the time of he accompany letter from one house to other house, and other example of is which can be presented by as a graph. Both example of above representing classic example of with theory graph which more knowledgeable with salesman traveling of problem or problem path shortest, which is on its principle look for short band from all place which must fulfill, so that can economize time, energy, and also expense. Graph in general can be defined as dot corps or nodes of vertices and line or arcs edges. Because line always early with an dot and terminated at other dot, hence line can be written down as couple between two dot.


Data structure at algorithm of programming there is some method, that is : stack, queue, tree, graph. Election used method very hinging with data, good in gathering process and also depository its.


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