Name
ST_GetFaceEdges — 返回一组绑定的有序边
aface
。
Synopsis
getfaceedges_returntype
ST_GetFaceEdges
(
varchar
atopology
, integer
aface
)
;
描述
返回一组绑定的有序边
aface
。每个输出由一个序列和edgeid组成。序列号以值1开头。
每个环形边的枚举从具有最小标识符的边开始。边的顺序遵循左侧规则(约束面位于每条有向边的左侧)。
可用性：2.0
This method implements the SQL/MM specification. SQL-MM 3 Topo-Geo和Topo-Net 3：例程详细信息：X.3.5
示例
-- 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;