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11dvincent Inglés 8 fichas

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1TableA collection of related information
2RecordsA record is all of the data on one thing or person
3FieldA field is one piece of information on one person or thing
4Data TypeMultiple pieces of data that can be put into a database such as number, date and time.
5Field LengthMost databases have a default field length such as 50 characters. But can be less for pieces of information like a postcode.
6Primary KeyEvery single record in a database has something different too identify it and this is a Primary Key.
7Foreign KeyA foreign key is sued too link tables together and create a relationship. This a field in one table that is linked to a primary key in another table
8Referential KeyEvery foreign key has a matching value to its corresponding primary key. Referential integrity uses these too ensure there are no orphan records i.e this prevents you from deleting related records.