空间操作
空间函数
sqala支持ISO/IEC 13249中定义的部分标准空间操作，支持MySQL和PostgreSQL的PostGIS插件。
| 函数 | 对应的SQL函数 |
|---|---|
stGeomFromText(a, srid) | ST_GeomFromText(a, srid) |
stAsText(a) | ST_AsText(a) |
stAsGeoJson(a) | ST_AsGeoJSON(a) |
stGeometryType(a) | ST_GeometryType(a) |
stX(a) | ST_X(a) |
stY(a) | ST_Y(a) |
stArea(a) | ST_Area(a) |
stLength(a) | ST_Length(a) |
stDistance(a, b) | ST_Distance(a, b) |
stContains(a, b) | ST_Contains(a, b) |
stWithin(a, b) | ST_Within(a, b) |
stIntersects(a, b) | ST_Intersects(a, b) |
stTouches(a, b) | ST_Touches(a, b) |
stOverlaps(a, b) | ST_Overlaps(a, b) |
stCrosses(a, b) | ST_Crosses(a, b) |
stDisjoint(a, b) | ST_Disjoint(a, b) |
stIntersection(a, b) | ST_Intersection(a, b) |
stUnion(a, b) | ST_Union(a, b) |
stDifference(a, b) | ST_Difference(a, b) |
stSymDifference(a, b) | ST_SymDifference(a, b) |