1. Selecting features in ArcMap
Data Queries
Selecting features in ArcMap

2. Data queries Important part of a GIS project
Can be a part of your data preparation or final analysis
Data Queries (selecting data based on a question or criteria)
Attribute Query
Spatial Data Query

3. Attribute Data Query
SQL (Structure Query Language) is used select records from an attribute table
Example of a SQL statement for retrieving data
Select *
From counties
Where NAME = Monterey
Query Expressions
Boolean expressions
Combination of field, a value, and a logical operator (=, +, - , etc..)
Boolean connectors (AND, OR, XOR, NOT)
Connects two expressions
The structure or syntax of sql consist of keywords that are strung together for form a statement. Here is a common SQL statement.

4. Query Expressions Expression Connectors
Combination of field (column), value, and an operator
Example:
Name = Monterey
Pop2000 >= 400,000
State_Name = Calfornia
Connectors
Keywords that connect two expressions
State_Name = California AND Pop2000>= 400,000
State_Name = California OR Pop2000>= 400,000

5. AND Connector State_Name = California AND Pop2000 >= 400,000
AND - satisfy both criteria - intersection

6. OR Connector State_Name = California OR Pop2000 >= 400,000
OR - satisfy either one or both criteria - union

7. Spatial Data Query 3 Ways to select features spatially (by location)
Feature selection by cursor - (select features tools)
Feature selection by graphic - (draw a graphic and use it to select features)
Feature selection by spatial relationship
Containment (fall within a feature)
Intersect (intersect a feature)
Proximity ( within a specified distance)

8. Working with selected features
create new selection
add to currently selected features
remove from currently selected features
select from currently selected features
You can add, remove or select from currently selected features using
location and attribute queries.

9. Isolating your selected features
Permanently save your selected features
save as new data file (shapefile or geodatabase)
Right-click on layer  data  Export data
Temporary save your selected features
create a temp layer in your ArcMap project as
Right-click on layer  selection  create layer from selected features
One extra step ….
--- to create a .lyr file
Right-click on layer Save As Layer File

10. Summary of selection types
Select by attribute using SQL
In ArcMap you can find this in the:
Selection menu
Attribute table
Definition query – displays data only
Located in the layer’s properties
Spatial Query:
Manually using the cursor
Select by graphics
Select by Location dialog