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SQL Geography Examples

Description

A simple portable SQL query using SQL::ResultSet::DataAsGeography, and an interactive session demonstrating DataAsGeography

Simple Portable SQL Query

Assuming that you are connected to the Airports SQL Server database, which has a Location field of type Geography:

SELECT id, Code, Name, City, County, State,  GeogLatitude(Location) AS Lat,  GeogLongitude(Location)  AS Lon( Elevation 
FROM US_Airports

Use of SQL::ResultSet::DataAsGeography

dim Result as C
dim cn as sql::Connection
dim Geography as A ' Note that we've dimmed this as A to show the true type.

if cn.open(ConnectionString)

  Result = Result + "Connection opened successfully." + crlf()
  cn.portableSQLEnabled = .t.

  if cn.execute("select GeogAsText(g.Location) from GeogTest g")
    Result = Result + "Query executed successfully." + crlf()
    ResultSet = cn.ResultSet

    Geography = ResultSet.DataAsGeography(1, 4326)
    Result = Result + "Geography object is of type: " + \
        typeof(Geography) + crlf()
    Result = Result + "Geography as XML: " + Geography.AsGML().Value + crlf()
    Result = Result + "Geography object as Text: " + \
        Geography.ToString() + crlf()
    Result = Result + "Geography Longitude: " + Geography.Long.Value + crlf()
    Result = Result + "Geography Latitude:  " + Geography.Lat.Value + crlf(2)
  else
    Result = Result  + "Error executing query: " + CurrentQuery + \
      crlf() + "Result is: " + cn.callresult.text + crlf(2)
  end if

else
  Result = Result  + "Error opening connection:: " \
   + ConnectionString + crlf() + "Result is: " + cn.callresult.text + crlf(2)
end if

showvar(Result)

An interactive session demonstrating DataAsGeography

Assuming you have run a SQL query that returns location as a Geography object in result set rs:

dim Geography as P
Geography = rs.DataAsGeography("Result is: ", 4326)

?Geography.Long.value
= -84.11936 
?Geography.Lat.value
= 33.811217

More samples can be found on Common Geography Database Tasks and many of the other pages listed below.

See Also