The document provides an overview of query layers and spatial views in ArcGIS, explaining their purpose and how to create them using SQL queries. It highlights practical use cases such as managing unique identifiers for parcels through centroid-based coordinates and the advantages of spatial views over traditional joins. The presentation also mentions technical requirements and offers examples of SQL commands for setting up query layers and spatial views.

1. Making Use of
Query Layers & Spatial Views
Michael Olkin
Town of Amherst, MA
www.amherstma.gov/maps

2. Technical Talk in Lightning Format
Will this work?

3. Query Layers & Spatial Views
• Data is Direct from your Databases
• Data Represented via SQL
• Work with ArcGIS for Desktop & Server*

4. What Are They?
Query Layer
•SQL Query
in ArcGIS
Desktop
Spatial View
•SQL Query
in your
relational
database

5. What Do They Do?
Query Layer
•Spatial Data
from tabular
sources
•Supports
ST_Geometry
Spatial View
•A View within
a Geodatabase
•Represents
existing spatial
data

6. Query Layer Use Case
• Scenario
– MassGIS Parcel
Standard unique
centroid-based
“LOC_ID”
– When I split a parcel, I
want to know whether
I need to change the
LOC_ID of the original
parcel

7. Show the LOC_ID Points via ST_Geometry
SELECT MAP_PAR_ID, LOC_ID,
CAST('POINT (' + CAST(CAST(substring(LOC_ID,3,6) as int) AS varchar) + ' ' +
CAST(CAST(substring(LOC_ID,10,7) as int) AS varchar) + ')' AS geometry) AS SHAPE,
'POINT (' + CAST(CAST(substring(LOC_ID,3,6) as int) AS varchar) + ' ' +
CAST(CAST(substring(LOC_ID,10,7) as int) AS varchar) + ')' as [ReadTheGeometry],
FROM <MyParcelFeatureClass>
X Y

8. Show the LOC_ID Points via ST_Geometry
SELECT MAP_PAR_ID, LOC_ID,
CAST('POINT (' + CAST(CAST(substring(LOC_ID,3,6) as int) AS varchar) + ' ' +
CAST(CAST(substring(LOC_ID,10,7) as int) AS varchar) + ')' AS geometry) AS SHAPE,
'POINT (' + CAST(CAST(substring(LOC_ID,3,6) as int) AS varchar) + ' ' +
CAST(CAST(substring(LOC_ID,10,7) as int) AS varchar) + ')' as [ReadTheGeometry],
FROM <MyParcelFeatureClass>
X Y

9. Create a Query Layer in ArcMap

10. Make a Query Layer with ArcToolbox
Data Management Tools -> Layers & Query Views -> Make Query Layer

11. Resulting Query Layer

12. Query Layer in Action
• Amherst Work Orders ArcGIS Online Map
Work Order Software
geocodes & stores X/Y
coordinates in a table

13. Yay! Query Layer Goodness!
Because every presentation needs a smiling cat

14. Spatial Views
• Warning! Legacy Solution for GDBs stored in a
RDBMS (ie., ArcSDE)
• More robust than an ArcGIS Desktop Join
• Requires ArcSDE Command Line Tools
(to be installed on the client)

15. Setting Up a Spatial View
• Command Line (ugh…ok, not so bad)
• Keep it simple on the setup; edit later
• GDB table registry references source feature class
sdetable -o create_view
-T <NewViewName>
-t <TheSpatialTable>,<TheJoinedTable>
-c SHAPE,<TheJoinedTable>.<Field1>,TheSpatialTable.<Field1>
-w "<TheJoinedTable>.<Field1> = TheSpatialTable.<Field1>"
-i sde:sqlserver:<InstanceName>
-D <DatabaseName>
-u <AdminUserName> -p <AdminPassword>

16. Spatial View: a regular database view
• Edit it in your database, like any other view
SELECT P.SHAPE,
ROW_NUMBER() OVER(ORDER BY c.PID) as OBJECTID,
C.PID,
P.Map_Lot,
C.PIN as MapBlockLot,
C.Location,
C.Number_Char as AddressNum,
C.Street,
C.Owner_Name
FROM <TheSpatialTable> AS P
LEFT OUTER JOIN <TheJoinedTable> AS C
ON P.Map_Lot = C.Map_Lot
SQL Server tsql example: ROW_NUMBER is used here to create a unique OBJECTID

17. Spatial View: One to Many Join!
• “Fake Out” ArcGIS with a clever query
– ArcGIS draws stacked features for duplicates if each one
has a unique OBJECTID
SELECT P.SHAPE,
ROW_NUMBER() OVER(ORDER BY c.PID) as OBJECTID,
C.PID,
P.Map_Lot,
C.PIN as MapBlockLot,
C.Location,
C.Number_Char as AddressNum,
C.Street,
C.Owner_Name
FROM <TheSpatialTable> AS P
LEFT OUTER JOIN <TheJoinedTable> AS C
ON P.Map_Lot = C.Map_Lot
SQL Server tsql example: ROW_NUMBER is used here to create a unique OBJECTID
ROW_NUMBER() OVER(ORDER BY c.PID) as OBJECTID,

18. Stacked Parcels with a Spatial View

19. Yay! Spatial View Goodness!
Because every presentation needs a smiling cat

20. Making Use of
Query Layers & Spatial Views
Michael Olkin
Town of Amherst, MA
www.amherstma.gov/maps