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Lookup tables are small tables used to store acceptable values for the data
entry fields in your database. Examples where you should use lookup tables are
for state names, name prefixes, name suffixes or/or a set of colors that your
database users may choose from.
You should use lookup tables where:
- There is a finite set of applicable values.
- You need to ensure that the values are
entered without spelling errors so you can later use the data as selection
criteria in queries or for grouping in reports.
To use lookup tables, you create listbox or
combobox controls in your user forms and then connect the value list of the
control to your lookup table. For combobox controls you should also limit data
input to values from the list. Listbox and combobox controls may allow you to
store the value list right within the control, instead of in a lookup table.
This might be OK for lookup tables with a few values that never change but
lookup tables allow you to easily edit the list and your administrative users
can maintain their own lists. If you store the list values right in the
control, your database users will need to come to you every time a value needs
to be addeded, edited or removed.
Lookup tables also allow you to create database
relationships that can then be used to prevent users from deleting lookup values that
are in use within the data tables.
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