Unit Two: Attribute Tables
In this unit…
►Review
►Opening
►Features
Tables
►Arranging
Moving
Windows
and




& properties
Basic features
Rearranging columns
Freezing & Sorting columns
Field Labels & Hiding fields
►Editing
Tables
 Entering Edit Mode (!?)
 Changing Attribute values
Review – GIS Data Types
►“Feature
Data”
 Data Structures:
►“Shapefiles”
►“Coverages”
►“Geodatabases”
 Examples:
►Lakes
►Houses
►Roads
Unit Two – Attribute Tables
►“Image
Data”
 Data Structures:
►image
e.g. “Digital Raster
Graphic” (DRG)
►“GRID”
►“Digital
Elevation
Model” (DEM)
 Examples:
►Aerial
photo
►Image of USGS topo
2
Review
Each “Record” in the table…
…Connected to a “Feature”
in the “Feature Data”
THIS is the heart
of GIS!
Unit Two – Attribute Tables
3
Review
Attribute Tables – Just Columns & Rows.
When tables contain the attributes of geospatial features,
the power of the data in the table is expanded… every
value can be represented graphically on a map!
Unit Two – Attribute Tables
4
Review
Opening an
Attribute
Table
We want “Attributes” of
a “Layer”, so…
Context is Layer
…right click and select
“Open Attribute Table”
Unit Two – Attribute Tables
5
Arranging and Moving Windows
Big change for
AV 3.x users!
Here’s the issue:
Learn to cope.
Unit Two – Attribute Tables
windows that you open
land on top and stay on top.
The Window menu is unlike
those you would find in
most other Windows
programs:
► no tiling,
► no cascading,
► no switching
between windows.
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Arranging and Moving Windows
But look… both
windows are “Active”
► You
You can always
minimize
windows…
They go to the
bottom of the
screen.
Unit Two – Attribute Tables
can take action in both
windows
►
Better: re-arrange the
windows altogether
►
Just drag them using the
title bar…
…and
► re-size them by dragging
the corners or borders.
7
Table Features and Properties
Basics
Table
Option
Menu
►
Click HERE to…
Make Column Active
►
and HERE to…
Select a Row
►
Some window features:
 Current record
 Record advance
 Show All / Show
Selected toggle
 Selected record
counter
 Options button
Unit Two – Attribute Tables
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Table Features and Properties
Rearranging
Columns
►
Click AND DRAG to…
Move Column left or right
►
Click and drag EDGES to…
Change Column Width
Unit Two – Attribute Tables
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Table Features and Properties
Freezing
and
►
Sorting
Unit Two – Attribute Tables
Context for Field
or data actions is
“Column” – rightclick in header
►
“freezing” - “unfreezing” toggle:
frozen columns stay on the left of
the table and do not scroll.
►
You can sort the “Active” column
from here as well.
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Table Features and Properties
Field Labels
and
Hiding Fields
Table context menus
don’t set ANY table
properties…
Instead: “Layer Context
Menu”… in the T.O.C. pane of
the ArcMap window
… right-click on the Layer…
and pick “Properties”
Unit Two – Attribute Tables
Population
… to change the field’s label,
enter a new alias here.
This checkbox makes the
field “4isible”.
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Your turn…
Chapter 2: Step 1 through 9
Unit Two – Attribute Tables
12
Editing Tables
Warning: You are now leaving the safe, virtual
ArcMap Environment.
Unit Two – Attribute Tables
13
Editing vs Data Definition
Know
what you
want!
Table
Option
Menu
Unit Two – Attribute Tables
Editing:
►
means changing attribute
values.
►
requires “Edit Mode”
Adding & Deleting Fields:
►
is not considered “Editing”
►
can’t be done in edit mode.
1.
Delete a field: the context is
an existing field, so right click
the field’s header.
2.
Add a Field: Options menu,
(no context) and complete the
field definition dialog.
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Adding Fields
Field Type Guidelines:
►
Use ‘text’ for fields that contain alpha, or numbers that won’t be
used for math
 Like zip codes: you don’t want the text ‘03824’ to display as a
number 3,824
►
Use ‘short’ or ‘long’ for integers (numbers that will require no
decimal places i.e. ‘scale’ = 0)
 ‘Short’ for numbers between -32,000 and +32,000
 ‘Long’ for numbers between about -2 billion and +2 billion
►
Use floating point for fractional numbers (require decimal places)
 Single floating point – aka ‘float’ – for precision < 7
 Double floating point – aka ‘double’ – for precision >6
Don’t worry too much: If you ask for the wrong kind of field, for the number
of decimal places requested, ArcGIS will pick the right field type for you.
Unit Two – Attribute Tables
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Editing Tables
Entering
Edit Mode
1. Add
the “Edit Toolbar”.
2. CLOSE
TABLES
THAT YOU WANT
TO EDIT FIRST!
3. Select
Editor Bar
appears
here…
But
can be
“docked
” here.
EDITOR MENU
Use the Edit Icon
or
► Use the selection
in the Tools Menu
or
► Right-click
anywhere in the
window margins
& pick “Editor”
►
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Editing Tables
Changing
Attribute
Values
Now that you’re in
Edit Mode:
What do you want to do?
►
Edit Cells
 Change one or two values?
►
Calculator
►
Selection
 Create new values that are
calculated from existing
ones?
►
Get out of
Edit Mode
 Change values in a set of
records that are all related
by common attribute value?
►
Get out of
Edit Mode
Unit Two – Attribute Tables
 Add a field?
 Delete a field?
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Editing Tables
Changing
Attribute
Values
►
Edit Cells
►
Calculator
►
Selection
To edit single
values, just
put the cursor
in the cell, and
type.
To calculate based on other values in the table,
right-click the header, select CALCULATE VALUES.
and enter a formula.
With no selected records: formula calculates how many
toes for every record...
..in this case there is one selected record so
the formula calculates only for that record.
BE CAREFUL WHAT IS SELECTED!!
Unit Two – Attribute Tables
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Your turn…
Chapter 2: Step 10 through END
Unit Two – Attribute Tables
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