PostGIS 1.5.8 Manual - Fedora Project Packages GIT repositories

PostGIS 1.5.8 Manual76 / 310Examples--Create a 3d line string from a 3d multipointSELECT ST_AsEWKT(ST_LineFromMultiPoint(ST_GeomFromEWKT(’MULTIPOINT(1 2 3, 4 5 6, 7 8 9)’))) ←↪;--result--LINESTRING(1 2 3,4 5 6,7 8 9)See AlsoST_AsEWKT, ST_Collect,ST_MakeLine7.3.16 ST_LineFromTextST_LineFromText — Makes a Geometry from WKT representation with the given SRID. If SRID is not given, it defaults to -1.Synopsisgeometry ST_LineFromText(text WKT);geometry ST_LineFromText(text WKT, integer srid);DescriptionMakes a Geometry from WKT with the given SRID. If SRID is not give, it defaults to -1. If WKT passed in is not a LINESTRING,then null is returned.NoteOGC SPEC 3.2.6.2 - option SRID is from the conformance suite.NoteIf you know all your geometries are LINESTRINGS, its more efficient to just use ST_GeomFromText. This just callsST_GeomFromText and adds additional validation that it returns a linestring.This method implements the OpenGIS Simple Features Implementation Specification for SQL 1.1. s3.2.6.2This method implements the SQL/MM specification. SQL-MM 3: 7.2.8ExamplesSELECT ST_LineFromText(’LINESTRING(1 2, 3 4)’) AS aline, ST_LineFromText(’POINT(1 2)’) ASnull_return;aline| null_return------------------------------------------------010200000002000000000000000000F ... | t←↪