ST_CompareWKT 方法

ST_SpatialRefSys::ST_CompareWKT(transform-definition-1,transform-definition-2)

名称	类型	说明
transform-definition-1	LONG VARCHAR	第一个空间参照系定义文本
transform-definition-2	LONG VARCHAR	第二个空间参照系定义文本

BIT 如果两个空间参照系逻辑上相等，则返回 1，否则返回 0。

确定两个空间参照系（由 WKT 定义）逻辑上是否相等。如果定义两个参照系的权限和标识符都相同，或者如果两个字符串完全相等，则这两个参照系被视为逻辑上相等。

SQL/MM (ISO/IEC 13249-3: 2006) 服务商扩充

以下示例显示，两个空间参照系被视为相等，即使这两个参照系具有不同名称：

SELECT  ST_SpatialRefSys::ST_CompareWKT(
    'GEOGCS["WGS 84",DATUM["WGS_1984",SPHEROID["WGS 84",6378137,298.257223563,AUTHORITY["EPSG","7030"]],AUTHORITY["EPSG","6326"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.01745329251994328,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4326"]]'
,   'GEOGCS["WGS 84 alternate name",DATUM["WGS_1984",SPHEROID["WGS 84",6378137,298.257223563,AUTHORITY["EPSG","7030"]],AUTHORITY["EPSG","6326"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.01745329251994328,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4326"]]'
) Considered_Equal

以下示例显示，两个空间参照系被视为不相等，因为这两个参照系是由不同权限定义的：

SELECT  ST_SpatialRefSys::ST_CompareWKT(
    'GEOGCS["WGS 84",DATUM["WGS_1984",SPHEROID["WGS 84",6378137,298.257223563,AUTHORITY["EPSG","7030"]],AUTHORITY["EPSG","6326"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.01745329251994328,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4326"]]'
,   'GEOGCS["WGS 84",DATUM["WGS_1984",SPHEROID["WGS 84",6378137,298.257223563,AUTHORITY["EPSG","7030"]],AUTHORITY["EPSG","6326"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.01745329251994328,AUTHORITY["EPSG","9122"]],AUTHORITY["AnotherAuthority","4326"]]'
) Considered_NotEqual

ST_CompareWKT 方法

语法

参数

返回值

注释

标准和兼容性

示例