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)
SQLite
st_linefromwkb (wkb blob, srid int32)
返回类型
ST_LineString
示例
以下命令创建表 (sample_lines),并使用 ST_LineFromWKB 函数从 WKB 表示插入线。该行将被插入到包含 ID 和使用 WKB 表示的空间参考系统 4326 中的线的 sample_lines 表中。
Oracle
PostgreSQL
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)', 4326)
);
INSERT INTO SAMPLE_LINES (id, geometry) VALUES (
1902,
sde.st_linestring ('linestring (33 2, 34 3, 35 6)', 4326)
);
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,4326)) 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 serial,
geometry sde.st_linestring,
wkb bytea
);
INSERT INTO sample_lines (geometry) VALUES (
sde.st_linestring ('linestring (850 250, 850 850)', 4326)
);
INSERT INTO sample_lines (geometry) VALUES (
sde.st_linestring ('linestring (33 2, 34 3, 35 6)', 4326)
);
--Replace ID values if necessary.
UPDATE sample_lines
SET wkb = sde.st_asbinary (geometry)
WHERE id = 1;
UPDATE sample_lines
SET wkb = sde.st_asbinary (geometry)
WHERE id = 2;
SELECT id, sde.st_astext (st_linefromwkb (wkb,4326))
AS LINE
FROM sample_lines;
id line
1 LINESTRING (850 250, 850 850)
2 LINESTRING (33 2, 34 3, 35 6)
SQLite
CREATE TABLE sample_lines (
id integer primary key autoincrement not null,
wkb blob
);
SELECT AddGeometryColumn (
NULL,
'sample_lines',
'geometry',
4326,
'linestring',
'xy',
'null'
);
INSERT INTO sample_lines (geometry) VALUES (
st_linestring ('linestring (850 250, 850 850)', 4326)
);
INSERT INTO sample_lines (geometry) VALUES (
st_linestring ('linestring (33 2, 34 3, 35 6)', 4326)
);
--Replace ID values if necessary.
UPDATE sample_lines
SET wkb = st_asbinary (geometry)
WHERE id = 1;
UPDATE sample_lines
SET wkb = st_asbinary (geometry)
WHERE id = 2;
SELECT id, st_astext (st_linefromwkb (wkb,4326))
AS LINE
FROM sample_lines;
id LINE
1 LINESTRING (850.00000000 250.00000000, 850.00000000 850.00000000)
2 LINESTRING (33.00000000 2.00000000, 34.00000000 3.00000000, 35.00000000 6.00000000)
相关主题
5/25/2014