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In the overwhelming majority of other cases it's better to explicitly maintain a separate child table to store the multiple selections. That was apparently added so Access could work better with SharePoint, and that is really the only time when that feature should be used.

You can still design your forms to have a combo box populated by the lookup table and bound to a field in the main table.)įor even more confusion, the Lookup wizard offers an "allow multiple selections" option so a field can hold more than one value (sort of). (When you maintain a "proper" separate lookup table your field in the main table shows what is actually in the field: the PK value for the selected item in the lookup table. You go to UPDATE tblName SET Size="Large"Īnd the query fails because it what you actually need to do is UPDATE tblName SET Size=3 When you look at the table you see the words, but the chances are good that the table really contains numbers like 1, 2, and 3. For example, say you have a Lookup field for with values 'Small', 'Medium' and 'Large'. They are really just a short-cut to having a "proper" lookup table and they hide what is really going on at the table level. The general consensus here seems to be that Lookup fields should be avoided. How to correctly minimize the number of times when the user has to type the data instead of choose the wanted item from the combo box.To understand when exactly should I use Access lookup wizard and when define a relationship between the tables.And, as a result, the user has to type all IDs manually, instead of choose them from the combo box. to link cityID from tblVoyage with tblCities/ cityID by lookup wizard, and let user choose the city from the combo box and not by typing specific city ID into the field.Įverything looks great, but there one confusing moment.ĭuring DB course I learnt, that in order to build a database and work with it, we have to define relationships between the tables (1:1, 1:M, M:N), but if I do it I can't use lookup wizard, because I've already defined relationships between tables. Microsoft Access has a built-in lookup wizard that allows to user to bind the table field with specific field from another table, e.g.

I need to avoid as much as possible the need to enter the values ID and let to user choose them from the combo box. One of the client's demands was to simplify the data entry process by using combo box with available values.įor example, instead of entering agentID the client asked to let the user choose agent name from the combo box, the same logic with other similar fields. I'm developing a Microsoft Access 2013 based information system.