Database intro
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A database is a collection of organized data that can be searched and accessed. Databases are used by many organizations to store and manage large volumes of records in an organized way. Each record contains multiple fields of information, and every record has a unique key field identifier to distinguish it from other records. Coding converts information into shorter values for efficient data storage, management, and analysis.
Database intro
- 1. DATABASES A database is a collection of data or information which is held together in an organized or logical way? In order to find the right web sites for you, Search engines need a vast computerized database which they search using your entered keywords. School use information systems to do registers and keep records on students. These contain a database with records for every student in the school. The database records student's attendance at school as well as information which may be needed by the school e.g. medical records or test scores.
- 2. DATABASES Databases are used by organizations such as governments, hospitals, utility companies and clubs as these databases allow for the storing, retrieving, editing and manipulating of large numbers of records. Libraries store details of all their books, in a database. When you want to know if a book is in stock, you can not only look it up, but you can also check when it is due to be returned. The database also records details of all the borrowers, what books they currently have borrowed and when they are due back
- 3. Tables The table allows you to see all of the records stored in the database. Tables can store many records, from a few dozen for a small database up to millions for a large company database Each table contains a lot of records.
- 4. Records DEFINITION: A record is all of the data or information about one person or one thing. In the table below, all of the information about each cartoon character is stored in a 'row' or 'record'. A record is made up of lots of individual pieces of information. Look at Wonder Woman's record: it stores her first name, last name, address, city and age.
- 5. Fields DEFINITION: a 'field' is one piece of data or information about a person or thing. The data type describes what data can be stored in the field e.g. Text, numbers, dates or Boolean (which means yes or no answers) . When you set up a database, you need to think about the 'data type' for each field.
- 6. Key Field Every record needs a identifier called the primary or key Field this is the field that contains a value which is unique to that record. For example we cannot use a name a key field for a student as there may be more that one student with the same name. So we use a Student ID or reference number.
- 7. CODING DEFINITION: CODING is the conversion of information into shorter values for the purpose of data storage, management, and analysis. E.G. the sex of the respondent may be coded "f” for a female and "m" for a male. This makes the information easier to enter, it reduces the chances of information being entered incorrectly and save time and space when enter information into a database.