Question

我正在尝试使用英国国家网格坐标为多边形创建一个质心以下是我的代码

CREATE TABLE PROJECT.CINEMAS
(CINEMA_ID INTEGER NOT NULL,
CINEMA_NAME VARCHAR(25) NOT NULL,
ADDRESS_NUMBER INTEGER NOT NULL,
POST_CODE VARCHAR(8) NOT NULL,
STREET VARCHAR (25) NOT NULL,
TOWN VARCHAR (25) NOT NULL,
OPENING_TIME TIME NOT NULL,
CLOSING_TIME TIME NOT NULL,
);

/* Add a geometry column containing point coordinates*/ 

SELECT ADDGEOMETRYCOLUMN('project','cinemas', 'COORDINATES_GEOM', '27700','POLYGON',2);

/* Create a cinema centroid geometry column

SELECT ADDGEOMETRYCOLUMN('project','cinemas', 'CENTROID', '27700','POINT',2);

INSERT INTO PROJECT.CINEMAS 
VALUES
(1,'ODEON LEICESTER SQUARE', 24, 'WC2H 7LQ', 'LEICESTER SQUARE', 'LONDON', '11:00:00 AM','11:00:00 PM',GeometryFromText('POLYGON((529901 180738,529944 180745, 529947 180717, 529906 180710, 529905 180719,529902 180718,529900 180727,529903 180729,529901 180738)',27700),ST_Centroid('POLYGON((529901 180738,529944 180745, 529947 180717, 529906 180710, 529905 180719,529902 180718,529900 180727,529903 180729,529901 180738)'));

为什么这不起作用的任何想法？

Answer 1

情侣，

你在POLYGON字符串

中忘记了结束了

应该是

GeometryFromText('POLYGON((529901 180738,529944 180745, 529947 180717, 529906 180710, 529905 180719,529902 180718,529900 180727,529903 180729,529901 180738))',27700)

在将值传递给st_centroid函数之前，您需要将多边形字符串转换为几何图形

ST_Centroid(GeometryFromText('POLYGON((529901 180738,529944 180745, 529947 180717, 529906 180710, 529905 180719,529902 180718,529900 180727,529903 180729,529901 180738))'))

... SO

INSERT INTO PROJECT.CINEMAS 
VALUES (1,'ODEON LEICESTER SQUARE', 24, 'WC2H 7LQ', 'LEICESTER SQUARE', 'LONDON', '11:00:00 AM','11:00:00 PM',
GeometryFromText('POLYGON((529901 180738,529944 180745, 529947 180717, 529906 180710, 529905 180719,529902 180718,529900 180727,529903 180729,529901 180738))',27700), 
ST_Centroid(GeometryFromText('POLYGON((529901 180738,529944 180745, 529947 180717, 529906 180710, 529905 180719,529902 180718,529900 180727,529903 180729,529901 180738))')));

Answer 2

如果错误是“解析错误 - 无效几何”，那么您的几何定义无效，需要修复它。

尝试分离几何体并执行SELECT以查看哪一个是错误的。我猜它是ST_Centroid的参数。

哦 - 然后，将PostgreSQL升级到至少 8.3.23 - 这仍然是不受支持的，但至少它有所有的bug修复。理想情况下升级到9.2。

如果您无法升级，请查看是否无法从此项目中删除 - 如果数据库损坏，那么您可能最终会对此负责。

Postgres 8.3.1质心

2 个答案: