Geography.FromWellKnownText
ValueTranslates text representing a geographic value in Well-Known Text (WKT) format into a structured record.
Syntax
Geography.FromWellKnownText(input as nullable text) as nullable recordParameters
| Name | Type | Required | Description |
|---|---|---|---|
input | text | Yes | A text value containing a geographic value in Well-Known Text (WKT) format. |
Return Value
record — A structured record representing the geographic value parsed from the WKT string, or null if the input is null.
Remarks
Geography.FromWellKnownText parses a Well-Known Text (WKT) string and returns a structured record representing a geographic value. WKT is a standard text format defined by the Open Geospatial Consortium (OGC) for representing spatial reference system objects. It is the typical serialization format used by databases including SQL Server.
Geographic values use a round-earth coordinate system based on latitude and longitude (as opposed to geometric values which use a flat Cartesian plane). The default spatial reference identifier (SRID) for geography types is 4326 (WGS 84), which is the standard used by GPS.
Common WKT geometry types include POINT, LINESTRING, POLYGON, MULTIPOINT, MULTILINESTRING, MULTIPOLYGON, and GEOMETRYCOLLECTION. For example, a point in Seattle might be represented as "POINT(-122.3321 47.6062)".
If the input is null, the function returns null.
Examples
Example 1: Parse a WKT point into a record
let
WKT = "POINT(-122.3321 47.6062)",
Result = Geography.FromWellKnownText(WKT)
in
Record.ToTable(Result)Example 2: Parse WKT geography values from a column
let
Source = #table({"City", "WKT"}, {
{"Seattle", "POINT(-122.3321 47.6062)"},
{"New York", "POINT(-74.006 40.7128)"}
}),
Parsed = Table.AddColumn(Source, "Geography", each Geography.FromWellKnownText([WKT]))
in
Parsed