Karteikarten
Database flashcards
Karten in diesem Stapel (8)
- 1TablesA table stores all of the records for a particular category.
- 2RecordsA record is all of the data or information about one person or one thing.
- 3FieldA 'field' is one piece of data or information about a person or thing.
- 4Data typesA data type is the type of data that you will use in a database. eg. numbers, text, currency, date/time, logical, Boolean, Yes/No
- 5Field LengthA field length is a limited amount of characters for a certain field. Minimum or maximum amounts of characters.
- 6Primary KeyA primary key is a unique set of characters that are set for certain people or objects, to help you identify what or who they are.
- 7Foreign KeyA foreign key is used to link tables together and create a relationship. It is a field in one table that is linked to the primary key in another table.
- 8Referential IntegrityEvery foreign key value has a matching value in the corresponding primary key.
Referential integrity uses these to ensure that there are no orphan records i.e. it prevents you from deleting related records. It can also alert you when you try and delete a certain record if it is linked to another record.
Informationen
- Beschreibung
- Karteikarten am Database flashcards, erstellt von 11choare am 11/11/2014.
- Erstellt von
- 11choare · Nov 2014
- Aktualisiert
- 19 Feb 2016
- Aufrufe
- 4
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