2.2.2.6 analyzes data for each table to delimit the information or fill out a field. 2.2.2.7 consider primary key field or fields (PrimaryKey) of each table. 2.2.2.8 data structure analysis based on the principle of Normalization in order to obtain a data table that has a complex structure and is not valid. 2.2.2.9 defines a data type (Data Type) that want to store that in any format. 2.2.2.10 define database relationships (Relationship) 2.2.2.11. the active screen. 2.2.3 the benefits of storing data is the database instead of the file is stored as a separate sub according to each job is causing many advantages as follows: 2.2.3.1 reduce duplication of data (Reduce Redundancy), because the data is stored as a single source, embodied not by isolation of machinery scattered storage, thus reducing the problem of duplication in the information store, which would waste time on data entry and storage space that repeatedly, including reduced backup costs. 2.2.3.2 data conflict mitigation (Reduce Inconsistence) storage that is smaller in various places on each job. When the data has been adjusted not to delete the information. Add or edit the information will all the same be done otherwise would cause problems or conflicting information. For example, when employees quit. Registration will remove the data of the employee from his or her data file. If registration is not received notification of such action to the other agencies. Know the internal data files of other divisions will continue to have a list of employees that are made to employee information does not match. But if you use the database system when the employee's registration data to delete data from a centralized database, so other agencies extract data from the same database can change instantly synchronize all your tasks, on the other hand, without requiring any update or copy the data over. 2.2.3.3 there independence between programs and storage information by creating a data file in a different computer languages are structured files that adhere to the format of the program that created it lacks independence continued to improve because of the need to develop the language according to the programming style of the language files are stored in the management database system is done through the database management system or DBMS, which compared Interlingua in contact can develop with the language or any other program that supports the use of standard language°.The SQL language, database systems, Lotto will also be able to contact and manage all the data in a database. 2.2.3.4 reduce data structure adjustment in developing programs in the original system. If there is a change in the data structure, such as adding headers or change the type of data stored will cause problems or risks may lead to damage of the system-wide information. In addition, such action must be made programmatically to a new management. Every time can be time-consuming and costly, while quite a lot if you use a database management system will be able to do it instantly, just order through DBMS without affecting or damaging the data stored. 2.2.3.5 a reliability database management system DBMS is the ability to validate the data entered by the storage condition is defined as, for example, requires that the input letters or numbers only, or to enter data in the interval that determines if a user enters invalid data in accordance with the terms of the DMBS systems without storage and send alerts to the user aware of until they enter a correct value according to the terms defined. 2.2.3.6 standard information. The information generated on standard database systems can be used extensively, such as in addition to use within an organization, it can also be used in the Internet system as well. With the benefit of current and future use 2.2.3.7 data security system The information in the database is secured by a DBMS system will be able to assign rights to access and manage each user's data is different. It helps prevent changes to the information, or any action which may cause damage to data from intruders, or who do not have sufficient privileges to perform it. 2.2.4 storage unit. How to store computer data will be stored in digital systems is stored as 1 and logic 0 logic State is comparable to the base figure 2 which contains the numbers 0 and 1 by the storage can be divided as follows: 2.2.4.1 bits (Bit) is the smallest storage unit. The meanings of the bits (Bit: Binary Digit) is the number of digits of the number 2, where each observation is only 1 and 0, 2 data status is 1, 10 or 11 is treated as a data bit 2. 2.2.4.2 byte (Byte) size 8-bit data refers to most of the data will be used in place of a character (Character) and size 1 KB (Kilo Byte) is equal to 1024 bytes. 2.2.4.3 field (Field) or field data is multiple bytes together to be used instead of storing something like name, address, salary, etc. 2.2.4.4 rekhod (Record), or is caused by a combination of various fields to convey the information store. 2.2.4.5 a file (File) is the unit of data that is caused by multiple information integration dama rekho. 2.2.4.6 database (Database) is to bring together data from several files together in order to share the process. A normal file 2.2.4.7 (Flat-Files Data Model) is that the files are stored separately as discrete files without a relationship. That is causing a problem, data duplication and conflict. Hierarchical 2.2.4.8 (Hierarchical Data Model) is a data storage in a complex relationship with nature in a child with parent (Parent and Child) is similar to the structure of files and folders to store Windows operating system is the main folder (Root) that contains the subfolder multiple folders, and each folder, it can create a subfolder. In the best of themselves. How is the relationship.
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