Creating Geometry Values Using WKT Functions

MySQL provides a number of functions that take as arguments a Well-Known Text representation and, optionally, a spatial reference system identifier (SRID). They return the corresponding geometry.

GeomFromText() accepts a WKT of any geometry type as its first argument. An implementation also provides type-specific construction functions for construction of geometry values of each geometry type.

• GeomCollFromText(wkt[,srid]), GeometryCollectionFromText(wkt[,srid])

  Constructs a GEOMETRYCOLLECTION value using its WKT representation and SRID.

• GeomFromText(wkt[,srid]), GeometryFromText(wkt[,srid])

  Constructs a geometry value of any type using its WKT representation and SRID.

• LineFromText(wkt[,srid]), LineStringFromText(wkt[,srid])

  Constructs a LINESTRING value using its WKT representation and SRID.

• MLineFromText(wkt[,srid]), MultiLineStringFromText(wkt[,srid])

  Constructs a MULTILINESTRING value using its WKT representation and SRID.

• MPointFromText(wkt[,srid]), MultiPointFromText(wkt[,srid])

  Constructs a MULTIPOINT value using its WKT representation and SRID.

• MPolyFromText(wkt[,srid]), MultiPolygonFromText(wkt[,srid])

  Constructs a MULTIPOLYGON value using its WKT representation and SRID.

• PointFromText(wkt[,srid])

  Constructs a POINT value using its WKT representation and SRID.

• PolyFromText(wkt[,srid]), PolygonFromText(wkt[,srid])

  Constructs a POLYGON value using its WKT representation and SRID.

The OpenGIS specification also defines the following optional functions, which MariaDB does not implement. These functions construct Polygon or MultiPolygon values based on the WKT representation of a collection of rings or closed LineString values. These values may intersect.

• BdMPolyFromText(wkt,srid)

  Constructs a MultiPolygon value from a MultiLineString value in WKT format containing an arbitrary collection of closed LineString values.

• BdPolyFromText(wkt,srid)

  Constructs a Polygon value from a MultiLineString value in WKT format containing an arbitrary collection of closed LineString values.

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