ST_GEOMETRYFROMWKB
描述
将一个标准图形 WKB（Well-known binary）转化为对应的内存的几何形式
别名
- ST_GEOMFROMWKB
语法
ST_GEOMETRYFROMWKB( <wkb>)
参数
| 参数 | 说明 |
|---|---|
<wkb> | 二进制形式的几何数据，通常由 ST_AsBinary 或其他 WKB 生成函数返回。支持所有标准几何类型（POINT、LINESTRING、POLYGON、CIRCLE几种集合类型 |
返回值
返回对应 WKB 表示的几何对象。如果输入为 NULL 或无效 WKB 格式，返回 NULL。
举例
POINT类型参数
select ST_AsText(ST_GeometryFromWKB(ST_AsBinary(ST_Point(24.7, 56.7))));
+------------------------------------------------------------------+
| st_astext(st_geometryfromwkb(st_asbinary(st_point(24.7, 56.7)))) |
+------------------------------------------------------------------+
| POINT (24.7 56.7) |
+------------------------------------------------------------------+
select ST_AsText(ST_GeomFromWKB(ST_AsBinary(ST_Point(24.7, 56.7))));
+--------------------------------------------------------------+
| st_astext(st_geomfromwkb(st_asbinary(st_point(24.7, 56.7)))) |
+--------------------------------------------------------------+
| POINT (24.7 56.7) |
+--------------------------------------------------------------+
LINE类型参数
select ST_AsText(ST_GeometryFromWKB(ST_AsBinary(ST_GeometryFromText("LINESTRING (1 1, 2 2)"))));
+------------------------------------------------------------------------------------------+
| st_astext(st_geometryfromwkb(st_asbinary(st_geometryfromtext('LINESTRING (1 1, 2 2)')))) |
+------------------------------------------------------------------------------------------+
| LINESTRING (1 1, 2 2) |
+------------------------------------------------------------------------------------------+
POLYGON类型参数
select ST_AsText(ST_GeometryFromWKB(ST_AsBinary(ST_Polygon("POLYGON ((114.104486 22.547119,114.093758 22.547753,114.096504 22.532057,114.104229 22.539826,114.106203 22.542680,114.104486 22.547119))"))));
+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| st_astext(st_geometryfromwkb(st_asbinary(st_polygon('POLYGON ((114.104486 22.547119,114.093758 22.547753,114.096504 22.532057,114.104229 22.539826,114.106203 22.542680,114.104486 22.547119))')))) |
+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| POLYGON ((114.104486 22.547119, 114.093758 22.547753, 114.096504 22.532057, 114.104229 22.539826, 114.106203 22.54268, 114.104486 22.547119)) |
+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
select ST_AsText(ST_GeomFromWKB(ST_AsBinary(ST_Polygon("POLYGON ((114.104486 22.547119,114.093758 22.547753,114.096504 22.532057,114.104229 22.539826,114.106203 22.542680,114.104486 22.547119))"))));
+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| st_astext(st_geomfromwkb(st_asbinary(st_polygon('POLYGON ((114.104486 22.547119,114.093758 22.547753,114.096504 22.532057,114.104229 22.539826,114.106203 22.542680,114.104486 22.547119))')))) |
+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| POLYGON ((114.104486 22.547119, 114.093758 22.547753, 114.096504 22.532057, 114.104229 22.539826, 114.106203 22.54268, 114.104486 22.547119)) |
+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
输入为NULL
mysql> SELECT ST_AsText(ST_GeometryFromWKB(NULL));
+-------------------------------------+
| ST_AsText(ST_GeometryFromWKB(NULL)) |
+-------------------------------------+
| NULL |
+-------------------------------------+
有效的的wkb格式
mysql> select ST_AsText(ST_GeometryFromWKB("\x010300000001000000050000000000000000002440000000000000000000000000000024400000000000002440000000000000000000000000000024400000000000000000000000000000000000000000000024400000000000000000"));
+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| ST_AsText(ST_GeometryFromWKB("\x010300000001000000050000000000000000002440000000000000000000000000000024400000000000002440000000000000000000000000000024400000000000000000000000000000000000000000000024400000000000000000")) |
+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| POLYGON ((10 0, 10 10, 0 10, 0 0, 10 0)) |
+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
无效的wkb格式
mysql> select ST_AsText(ST_GeometryFromWKB("\010300000001000000050000000000000000002440000000000000000000000000000024400000000000002440000000000000000000000000000024400000000000000000000000000000000000000000000024400000000000000000"));
+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| ST_AsText(ST_GeometryFromWKB("\010300000001000000050000000000000000002440000000000000000000000000000024400000000000002440000000000000000000000000000024400000000000000000000000000000000000000000000024400000000000000000")) |
+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| NULL |
+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
