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SOME IMPORTANT TERMS & DATATYPES OF DATABASE

The working of a Database starts with creation of tables. There are different elements in database package, all of which work together to make the database package function. Each element has a specific role to play. Some of them:-
1. Field Name: A field name is the identifier of a field as it contains the data that is to be stored in that field. It may consist of letters, numbers and special characters.
"It is the name of the column of a table."
2. Field Type: Field type or Data type signifies the type of data which will be entered in a particular field.
3. Properties: Field properties signify the behavior of the field. It helps in keeping the consistency of the data entered by the user.
4. Queries: Queries are the format of requirement of information that can be received on the basis of records stored in a table.
5. Forms: Forms are the layout for the entry of data. They are used as format to let the operatior feed/input data for creating records in a table.
6. Report: Reports are used to get or print the information from the database. They are based on the information found in tables as per the queries.
7. Primary Key: Primary key is the name of a field that uniquely identifies a record in a table. There can be only one(unique) primary key in the table.

DATATYPES IN DATABASE 

A database stores different types of data so a clear distinction has to be made between types of data for proper identification and for the kind of manipulation to be done on data. Data type of the field specifies what type or kind of data is to be stored in a particular field so that the respective kind of operations can be done on that data.
Some common data types are:-
Text: A field of this data type can store text or combination of text and numbers or numbers on which calculations cannot be done.
Numeric: A field of this data type can store numbers from zero to nine(0-9) or its combination on which calculations can be done.
Date/Time: A field of this type of data can store the date and time values.
Auto Number: A field of this data type automatically gets the value when a new record is added is added in a table. One cannot update or change the value of this type of field.
Yes/No: A field of this data type can store'Yes/No' or 'True/False' values. It is also called as Boolean data type.

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