ST_GEOMFROMGEOHASH

📄字数 856

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功能描述

从 GeoHash 字符串返回边界的多边形。

语法格式

GEOMETRY ST_GEOMFROMGEOHASH(CLOB geohash, INTEGER precision=NULL);

参数说明

• geohash：GeoHash 字符串。
• precision：精度。可选，默认值：完整精度。

函数返回类型

GEOMETRY 类型

使用说明

1. 未指定precision，返回基于输入 GeoHash 字符串的完整精度的多边形。
2. 指定precision，使用 GeoHash 中的许多字符来创建多边形。

示例

SQL> SELECT TO_CHAR(ST_ASTEXT(ST_GEOMFROMGEOHASH('9qqj7nmxncgyy4d0dbxqz0')));

+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
|                                                                                  EXPR1                                                                                   |
+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| POLYGON((-115.17281600000001 36.11464599999999,-115.17281600000001 36.114646,-115.172816 36.114646,-115.172816 36.11464599999999,-115.17281600000001 36.11464599999999)) |
+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------+

SQL> SELECT TO_CHAR(ST_ASTEXT(ST_GEOMFROMGEOHASH('9qqj7nmxncgyy4d0dbxqz0', 4)));

+------------------------------------------------------------------------------------------------------------------------------+
|                                                            EXPR1                                                             |
+------------------------------------------------------------------------------------------------------------------------------+
| POLYGON((-115.3125 36.03515625,-115.3125 36.2109375,-114.9609375 36.2109375,-114.9609375 36.03515625,-115.3125 36.03515625)) |
+------------------------------------------------------------------------------------------------------------------------------+


SQL> SELECT TO_CHAR(ST_ASTEXT(ST_GEOMFROMGEOHASH('9qqj7nmxncgyy4d0dbxqz0', 10)));

+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
|                                                                                                  EXPR1                                                                                                   |
+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| POLYGON((-115.17282128334045 36.11464083194733,-115.17282128334045 36.114646196365356,-115.1728105545044 36.114646196365356,-115.1728105545044 36.11464083194733,-115.17282128334045 36.11464083194733)) |
+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+