Database Summary
Databases consist of 1 or more files (or tables). Files are made up of records.
Records consist of 1 or more fields, basically information about something.
Key fields make a record unique, e.g. a customer number.
Fields contain different data types including Text, Integer, Real number, Yes/No (Boolean), Date, Time, Sound, and Video
Fields can be fixed or variable length. Fixed length fields search faster; variable fields take up less disk space.
Coding data speeds up data entry and helps avoid mistakes. e.g. instead of entering child or adult, code as c and a in the appropriate field.
Databases are searched with simple or complex queries. Simple queries search on a single field. Complex queries can search more than one field on a combination of terms.
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