Microsoft Access 2010 Bible

Chapter 2: Creating Access Tables

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FIGURE 2.21

The Table Design View area on the Options screen contains options for setting the AutoIndex on Import/
Create specifier.

When to index

Generally speaking, you should index fields that are frequently searched or sorted. Remember that

indexes slow down certain operations such as inserting records and some action queries.

Memo and OLE Object fields can’t be indexed. It would be impossible for Access to maintain an

index on these complete data types.

An index should not be used if a field contains very few unique values. For example, you won’t see

a significant benefit from indexing a field containing a person’s sex or state, or Yes/No fields.

Because there is a limited range of values in such fields, Access easily sorts the data in these fields.

Use a multiple-field index in situations where sorts are often simultaneously performed on multi-

ple fields (for example, first and last names). Access will have a much easier time sorting such a

table.

Understanding tblCustomers Field

Properties

After you enter the field names, data types, and field descriptions, you may want to go back and

further refine each field. Every field has properties, and these are different for each data type. In

tblCustomers, you must enter properties for several data types. Figure 2.22 shows the property

area for the field named CreditLimit. Notice that there are two tabs on the property box —

General and Lookup.

Tip
Figure 2.22 shows 11 properties available for the CreditLimit Currency field. Other types, such as
Number and Date/Time, Text, or Yes/No show more or fewer options.