How to Create a Data Dictionary?
Data Dictionary can be formed with the help of the following relational database like MySQL, SQL Server, etc. Several notations are present everywhere which enhances the quality of the Data Dictionary. We will also look into that. Database Administrators can have the following templates like SQL Server, that help in making Data Dictionary.
Notations in Data Dictionary
Data Construct | Notation | Meaning |
---|---|---|
Composition | = | Is composed of |
Sequence | + | Represents AND |
Selection | [ |] | Represents OR |
Repetition | { }n | Represents n repetitions or repetition for n times |
Parentheses | ( ) | Optional data that may or may not be present |
Comment | *…* | Delimits a comment or commented information |
Example: Let us understand this by taking an example of the reservation system. In the reservation system, “passenger” is a data item whose information is available on the data dictionary as follows:
Keys | Values |
---|---|
Name | Passenger |
Aliases | None |
Where or how it’s used? | Passenger’s query (input) Ticket (output) |
Description |
|
Short Note on Data Dictionary
A Data Dictionary comprises two words i.e. Data which simply means information being collected through some sources and Dictionary means where this information is available.
A Data Dictionary can be defined as a collection of information on all data elements or contents of databases such as data types, and text descriptions of the system. It makes it easier for users and analysts to use data as well as understand and have common knowledge about inputs, outputs, components of a database, and intermediate calculations.