Kexi/Handbook/Introduction to Databases/What Is a Database: Difference between revisions

Latest revision as of 22:07, 25 December 2024

What Is a Database?

You can define a database as a collection of data on one topic. It is organised in a way allowing to easily browse the information, make changes or add new items.

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:

Contacts 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, real databases usually need more than one table.

To sum up, you have already got a simple database with one table Contacts.

@@ Line 6: / Line 6: @@
 Look at this diagram for one of the above examples: a simple phone book.
+[[File:Kexi_contact_example.png|center]]
+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:
+{| class="wikitable" style="margin:auto;max-width:20rem;"
+|+ Contacts 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, real databases usually need more than one table.
+To sum up, you have already got a simple database with one table ''Contacts''.
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