Points to Line

Draft: written, not yet checked by a person Operation · points-to-line

Joins a layer's points, in order, into a line.

Pitfall. The line follows the points' order; without an order field or expression, that is whatever order the engine reads them in.

Pitfall. Engines differ on how they make one line per group (a field, an expression, or a GROUP BY).

About this operation
Also called	Points To Line, points to path, make line, connect points
Group	`vector/geometry`
Checks	`geometry.valid`
Pitfalls	2 listed above
Columbus tool	Not stated
Notes	Not stated
Status	active
Broader	Not stated
Narrower	Not stated
Related	`extract-vertices` `lines-to-polygons`

Parameters

Not stated

Direction	Name	Type	Geometry	Note
Input	`layer`	vector	point	Not stated
Output	`output`	vector	line	Not stated

Engine	Tool	Parameters	Differences
`apache-sedona`	`sedona.sql.ST_MakeLine`	`layer` → `geom1`	Joins two geometries (geom1, geom2) or an array of points; collect the points first. A Spark SQL function: arguments are columns or column names, run over a Spark DataFrame.
`postgis`	`st_makeline`	`layer` → `#1`	As an aggregate, ST_MakeLine(geom ORDER BY field) joins a group's points; without ORDER BY the order is not guaranteed.
`qgis`	`native:pointstopath`	`layer` → `INPUT` `output` → `OUTPUT`	ORDER_EXPRESSION sets the order and GROUP_EXPRESSION makes one line per group; CLOSE_PATH joins the last point back to the first.