Kexi/Handbook/Introduction to Databases/What Is a Database?/da: Difference between revisions
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=== Hvad er en database? === | === Hvad er en database? === | ||
Du kan definere en database som en samling af data om et emne. Den er organiseret på en måde, som gør det let at bladre igennem informationen, foretage ændringer og tilføje nye emner. | |||
Look at this diagram for one of the above examples: a simple phone book. | Look at this diagram for one of the above examples: a simple phone book. | ||
Revision as of 11:50, 22 June 2012
Hvad er en database?
Du kan definere en database som en samling af data om et emne. Den er organiseret på en måde, som gør det let at bladre igennem informationen, foretage ændringer og tilføje nye emner.
Look at this diagram for one of the above examples: a simple phone book.
The above picture shows a set of two contacts each of which is presented on a separate card. It appears that such a card can constitute a single row in a table:
| Name | Tel No. |
|---|---|
| Joan | 699 23 43 12 |
| Adam | 711 19 77 21 |
Terms and definitions: A single data which constitutes a part of a greater collection can be called a row or more professionally a record. The collection is normally called a table. Moreover, the most natural name for the table is one describing the data it offers/stores which is Contacts. Furthermore, each row in the table consists of columns often also called fields. In the table Contacts there are two columns (fields): Name and Tel No..
For simple uses a single table can make up a database. Many people consider these two equivalent. As you will see, for real databases we usually need more than one table.
To sum up, you have already got a simple database with one table Contacts.
Note