Information handling/Databases

Information handling/Databases

1. the uses of databases

   • store data
   • organise data
   • update (easier) data
   • Delete data
   • searching data
   • sorting data
   • Query signs

2. Data types

3. Data structure

   • fields
   • records
   • files

4. keyfields (unique id)

5. computerised databases

   • can hold a vast amount of data
   • can analyse data
   • can search for a specific criteria
   • can easily make a back up
   • can easily update asnd delete records
   • reconds stored safely and accessed when needed
   • can search very fast for certain records

6. Validation checks

   • lists
     • you are forced to make a choice form a drop down list, so unallowed data can not be entered
   • Range check
     • Range check can make sure only sensible data is entered. in an order, it would not mkake sense to add a quanrity of zero, so a rnage check of '>0' (greater than zero) copuld be added
   • format checks
     • These are used to check the that the correct combination of letters and numbers are entered Input masks can be used for format checking.

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