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As many as ten fields can be included in a composite index. As long as the composite index is not
used as the table??™s primary key, any of the fields in the composite index can be empty.
Figure 2-26 shows how to set the properties of a composite index. The cursor is placed in the row
in the Indexes dialog box containing the name of the index. Any row appearing immediately below
this row that does not contain an index name is part of the composite index. Notice the three properties
appearing below the index information in the top half of the Indexes dialog box.
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Access Building Blocks Part I
FIGURE 2-26
It??™s easy to set the properties of a composite index.
The index properties are quite easy to understand:
n Primary: When set to Yes, Access uses this index as the table??™s primary key. More than
one field can be designated as the primary key, but keep the rules governing primary keys
in mind, particularly those requiring each primary key value to be unique and that no field
in a composite primary key can be empty.


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