Using ArcCatalog

Adding and
deleting
attributes
Adding an attribute
1. Click the shapefile or dBASE
table to which you want to
add an attribute.
2. Click the File menu and click
Properties.
3. Click the Fields tab.
4. Scroll down until you see the
last attribute.
5. Click in the empty row below
the last attribute under Field
Name and type the name of
the new attribute.
6. Click under Data Type next to
the new attribute name. A
dropdown list appears with
the Text data type selected by
default. Click the appropriate
data type in the list for the
new attribute.
The properties that are
appropriate for the new
attribute’s data type appear in
the Field Properties list
below.
7. Click in the Field Properties
list and type the properties for
the new attribute.
For example, if the data type
is a real number, set the
precision—the total number
of digits the values can
have—and scale—the total
number of decimal places the
values can have—properties.
8. Click OK.
The Catalog lets you modify the
structure of shapefiles and
dBASE tables by adding and
deleting attribute columns. The
name and data type of an
existing column can’t be
modified; instead, you must add
a new column with the appropriate
name and data type. A
column’s name must be no more
than 10 characters in length;
additional characters will be
truncated. A shapefile’s FID and
Shape columns and a dBASE
table’s OID column can’t be
deleted. The OID column is a
virtual column created by
ArcGIS software when accessing
the table’s contents; it
guarantees that each record in
the table has at least one
unique value. Shapefiles and
dBASE tables must have at
least one attribute column in
addition to the FID and Shape
columns or the OID column.
After adding attributes, you
must start an edit session in
ArcMap to define their values.
5
6
7
180 USING ARCCATALOG