ST_EqualsFilter method for type ST

geometry-expression.ST_EqualsFilter(geo2)

Name	Type	Description
geo2	ST_Geometry	The other geometry value that is to be compared to geometry-expression.

BIT Returns 1 if the bounding box for geometry-expression is equal, within tolerance, to the bounding box for geo2, otherwise 0.

The ST_EqualsFilter method provides an efficient test to determine if a geometry might be equal to another. ST_EqualsFilter returns 1 if geometry-expression might be equal to geo2; otherwise ST_EqualsFilter returns 0.

This test is cheaper than ST_Equals, but can return 1 in some cases where the geometry-expression is not actually equal to geo2.

Therefore, This method can be useful as a primary filter when further processing will determine whether geometries interact in the desired way.

The implementation of ST_EqualsFilter relies upon meta-data associated with the stored geometries. Because the available meta-data may change between server versions, depending upon how the data is loaded, or where ST_EqualsFilter is used within a query, the expression geometry-expression.ST_EqualsFilter(geo2) can return different results when geometry-expression does not equal geo2. Whenever geometry-expression equals geo2, ST_EqualsFilter will always return 1.

SQL/MM (ISO/IEC 13249-3: 2006) Vendor extension

ST_EqualsFilter method for type ST_Geometry

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Standards and compatibility