ST_LineFromWKB

定义

ST_LineFromWKB 以 ST_LineString 类型的熟知二进制 (WKB) 表示和空间参考 ID 作为输入，返回 ST_LineString 类型的对象。

语法

Oracle

sde.st_linefromwkb (wkb blob, srid integer)

PostgreSQL

sde.st_linefromwkb (wkb bytea, srid integer)

返回类型

ST_LineString

示例

在以下示例中，对结果行进行了重新格式化，以增强可读性。结果中的间距将根据在线显示而有所不同。下列代码使用 ST_LineFromWKB 函数基于 WKB 表示创建和插入线。该行将被插入到包含 ID 和使用 WKB 表示的空间参考系统 1 中的线的 sample_lines 表中。

Oracle

CREATE TABLE sample_lines (id smallint, geometry sde.st_linestring, wkb blob);

INSERT INTO SAMPLE_LINES (id, geometry) VALUES (
1901,
sde.st_linestring ('linestring (850 250, 850 850)', 0)
);

INSERT INTO SAMPLE_LINES (id, geometry) VALUES (
1902,
sde.st_linestring ('linestring (33 2, 34 3, 35 6)', 0)
);

UPDATE SAMPLE_LINES
SET wkb = sde.st_asbinary (geometry)
WHERE id = 1901;

UPDATE SAMPLE_LINES
SET wkb = sde.st_asbinary (geometry)
WHERE id = 1902;

SELECT id, sde.st_astext (sde.st_linefromwkb (wkb,0)) LINE
FROM SAMPLE_LINES;

ID   LINE 

1901 LINESTRING (850.00000000 250.00000000, 850.00000000 850.00000000) 
1902 LINESTRING (33.00000000 2.00000000, 34.00000000 3.00000000, 35.00000000 6.00000000)

PostgreSQL

CREATE TABLE sample_lines (id integer, geometry sde.st_linestring, wkb bytea);

INSERT INTO sample_lines (id, geometry) VALUES (
1901,
sde.st_linestring ('linestring (850 250, 850 850)', 0)
);

INSERT INTO sample_lines (id, geometry) VALUES (
1902,
sde.st_linestring ('linestring (33 2, 34 3, 35 6)', 0)
);

UPDATE sample_lines
SET wkb = sde.st_asbinary (geometry)
WHERE id = 1901;

UPDATE sample_lines
SET wkb = sde.st_asbinary (geometry)
WHERE id = 1902;

SELECT id, sde.st_astext (st_linefromwkb (wkb,0)) 
AS LINE
FROM sample_lines;

id   line 

1901 LINESTRING (850 250, 850 850) 
1902 LINESTRING (33 2, 34 3, 35 6)