GEOGRAPHY DATATYPES in SQL Server. by jared nielsen linkedin.com/nielsendata

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1 GEOGRAPHY DATATYPES in SQL Server by jared nielsen linkedin.com/nielsendata

2 GEOGRAPHY vs GEOMETRY Geography Plots ellipsoidal Round Earth data using latitude, longitude and altitude* coordinates Geometry Plots polygonal, geometric and linear data using X, Y and Z* coordinates * not implemented well

3 Measuring the Earth Coordinates Longitude = X Latitude = Y Altitude = Z

4 Measuring the Earth Ranges Longitude = 0 to 360 Latitude = 90 to -90 Altitude = 0 to (ft)

5 World Geodetic System Global standards body that defines the coordinate systems for Earth The latest revision is WGS 84 - referred to as EPSG:4326

6 EPSG: 4326 This geodetic standard is specified in many geography datatype queries: UPDATE SQLDevelopers SET GeoPosition = geography:: Point( , , 4326)

7 BASIC GIS CONCEPTS Well Known Text ESRI Shape and Data Sources

8 Well Known Text - WKT Type Example Convert to Spatial Point Point(x,y).STPointFromText() MultiPoint MultiPoint( (x,y), (x,y) ).STMPointFromText() LineString LineString( x y, x y, x y).stlinefromtext() MultiLineString MultiLineString( (x y, x y) (x y, x y) ).STMLineFromText() Polygon Polygon ( (x1 y1, x2 y2, x3 y3, x1 y1) ).STPolyFromText() MultiPolygon You get the idea Keep using those parenthesis.stmpolyfromtext()

9 How LONG is your LAT? Sometimes you should use LON/LAT (WKT) Other times you need to use LAT/LON (SQL) LAT LON San Jacinto College = , SET GeoPosition = geography:: STGeomFromText('POINT( )', 4326) SET GeoPosition = geography:: Point(29.578, , 4326)

10 Get Some Data Positions for the International Space Station: Global Country Maps: Zip Codes, School Districts, Demographics: Railroads, Rivers, Cities, Volcanoes:

11 ESRI Shapefile Converters Convert ESRI Shapefiles to SQL Geography: Queries SQL Geography to a Map: ESRI Metadata Translation: java/gp_toolref/conversion_tools/ esri_metadata_translator_conversion_.htm

12 SQL SERVER SPATIAL Make a Table Load Data Query Spatial-ly

13 Making a Table CREATE TABLE dbo.issposition( Longitude decimal(18, 15) NULL, Latitude decimal(18, 15) NULL, Sampled datetime NULL, LocalTime nvarchar(50) NULL, GeoPosition geography NULL, GeomShape geometry NULL )

14 Loading Data INSERT INTO ISSPosition (Sampled, Longitude, Latitude, LocalTime) VALUES ('01/01/ :00:00',-125.4,41,'15:38:18 ) Naturally I loaded more data one data point per minute from January 1 to present It turns out that the Space Station falls fast at 17,136 mph

15 Convert to Geography UPDATE ISSPosition SET GeoPosition = geography:: Point([Latitude], [Longitude], 4326) GO (note we are using the native SQL Point method so we keep LAT/LON)

16 Query our Data select top 180 * from dbo.issposition Not the most thrilling outcome Let s try the Spatial Results Tab

17 Spatial Results Tab select top 180 * from dbo.issposition Still not that exciting a bunch of dots

18 Space Station Orbit select top 180 * from dbo.issposition order by Sampled Now we are getting somewhere!

19 Comma Delimited Points nvarchar(max) = STUFF((SELECT TOP 180 ',' + Convert(nvarchar(25),Longitude) + ' ' + Convert(nvarchar(25),Latitude) FROM dbo.issposition ORDER BY Sampled FOR XML PATH('')),1,1,'')

20 Convert Points to LineStrings geography = geography::stlinefromtext('linestring(' +@ISSOrbitWKT+')',4326)

21 Space Station Orbit Now you have connected points in a linestring showing the orbit

22 Space Station Orbit CREATE TABLE CoolShapes( Name Nvarchar(100) NOT NULL, GeoShape geography NULL) GO INSERT into CoolShapes (Name, GeoShape) values ( ISS Orbital Path,@ISSOrbit) I like this shape so much I m going to keep a copy of it

23 World Geography Global Datasets From ESRI Shapefiles

24 Load Global Maps

25 Load Global Maps union all select GeoMap from dbo.world With a UNION, we simply plot the orbit on the Global ESRI Shapefile Map

26 GEOGRAPHY Case Studies INTERSECTION BUFFERS

27 Spatial Methods Type Example Syntax Intersect Distance Crosses Within

28 STIntersection Method UNION ALL SELECT GeoMap FROM World WHERE Name='China' A human knows that the orbit crosses China, but how do we tell the computers?

29 STIntersection Method SELECT We know it intersects but WHERE?

30 STIntersection Method SELECT Can you see them?

31 STIntersection Method SELECT UNION ALL Let s add a few.stbuffer(s)

32 MAKING IT LOCAL San Jacinto College

33 Make Some Developers insert into SQLDevelopers (Name, Latitude, Longitude, Altitude) values ('Jared Nielsen Dark Matter', , , 15) insert into SQLDevelopers (Name, Latitude, Longitude, Altitude) values ('Jared Nielsen', , , 15) insert into SQLDevelopers (Name, Latitude, Longitude, Altitude) values ('Nancy Hidy Wilson', , , 14) insert into SQLDevelopers (Name, Latitude, Longitude, Altitude) values ('Robert Gremillion', , ,16) UPDATE SQLDevelopers SET GeoPosition = geography::point([latitude], [Longitude], 4326) GO

34 San Jacinto College is Cool ALTER TABLE CoolShapes ADD GeoPosition geography NULL GO INSERT INTO CoolShapes (Name, GeoPosition) VALUES ('San Jacinto College', geography::point( , , 4326))

35 STIntersection Method SELECT GeoPosition.STBuffer(100) FROM CoolShapes WHERE Name='San Jacinto College' UNION ALL SELECT GeoPosition.STBuffer(30) FROM SQLDevelopers One Developer is Not Attending

36 STIntersection Method SELECT GeoPosition.STBuffer(100) FROM CoolShapes WHERE Name='San Jacinto College' UNION ALL SELECT GeoPosition.STBuffer(30) FROM SQLDevelopers WHERE NAME NOT IN ('Robert Gremillion') Who else is here?

37 More Methods geography geography geography Geography geography = GeoPosition.STBuffer(5) FROM SQLDevelopers WHERE Name = 'Jared Nielsen' = Geoposition.STBuffer(5) from SQLDevelopers WHERE Name='Robert Gremillion' = Geoposition.STBuffer(5) from SQLDevelopers where Name LIKE 'Nancy%' = Geoposition.STBuffer(100) from CoolShapes WHERE Name = 'San Jacinto College' = Geoposition.STBuffer(2) from SQLDevelopers WHERE Name = 'Jared Nielsen Dark Matter

38 More Methods SELECT = Boolean True SELECT = Boolean False SELECT = meters geography Do I stink?

39 More Methods Boolean = 1

40 JARED NIELSEN Serial Entrepreneur Investor Software Architect Questions?

Mississippi Private Schools 2015

Mississippi Private Schools 2015 Shapefile Tags education, schools, private, K-12 Summary To add to state data clearinghouse the Mississippi private schools point features. Description Point locations