ST_GetFaceEdges
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## Name

ST_GetFaceEdges — Returns a set of ordered edges that bound `aface`.

## Synopsis

`getfaceedges_returntype ST_GetFaceEdges(`varchar atopology, integer aface`)`;

## Description

Returns a set of ordered edges that bound `aface`. Each output consists of a sequence and edgeid. Sequence numbers start with value 1.

Enumeration of each ring edges start from the edge with smallest identifier. Order of edges follows a left-hand-rule (bound face is on the left of each directed edge).

Availability: 2.0

This method implements the SQL/MM specification. SQL-MM 3 Topo-Geo and Topo-Net 3: Routine Details: X.3.5

## Examples

    -- Returns the edges bounding face 1
    SELECT (topology.ST_GetFaceEdges('tt', 1)).*;
    -- result --
     sequence | edge
    ----------+------
            1 |   -4
            2 |    5
            3 |    7
            4 |   -6
            5 |    1
            6 |    2
            7 |    3
    (7 rows)

    -- Returns the sequence, edge id
    -- and geometry of the edges that bound face 1
    -- If you just need geom and seq, can use ST_GetFaceGeometry
    SELECT t.seq, t.edge, geom
    FROM topology.ST_GetFaceEdges('tt',1) As t(seq,edge)
    	INNER JOIN tt.edge AS e ON abs(t.edge) = e.edge_id;

## See Also

GetRingEdges, AddFace, ST_GetFaceGeometry

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