ST_EqualsIdentical

Introduction: Returns true if A and B have identical geometry types, component ordering, coordinate ordering, dimensionality, and coordinate values.

Unlike ST_EqualsExact, this predicate does not accept a tolerance. NaN ordinate values are considered equal to other NaN values. The SRID and other geometry metadata are not compared.

Format: ST_EqualsIdentical(A: Geometry, B: Geometry)

Return type: Boolean

Since: v2.0.0

This function supports Snowflake GEOMETRY values. It is not available for GEOGRAPHY values. Snowflake currently stores native GEOMETRY values as two-dimensional coordinates with 14 decimal places, so identity is evaluated on those stored 2D values.

Visual example

The inputs are shown separately so their traversal direction and container structure are easy to compare. Geometries can occupy the same locations and still be non-identical when their vertex order, geometry type, or nesting differs.

The Z/M visual used by the Spark and Flink pages does not apply to native Snowflake GEOMETRY values because Snowflake stores those values in two dimensions.

Choosing an equality predicate

Predicate	Comparison	Typical use
ST_Equals	Same two-dimensional topology; representation and ordering may differ	Find geometries that describe the same shape
ST_EqualsExact	Same structure and order, with corresponding stored coordinates within a tolerance	Accept small representation differences
ST_EqualsIdentical	Same type, structure, order, and exact stored coordinate values	Verify that a stored 2D geometry representation was preserved

ST_EqualsIdentical does not compare SRID or other geometry metadata. The Snowflake GeoJSON UDF bridge also does not carry SRID into the predicate, so compare CRS metadata separately when it is part of the validation contract.

SQL examples

Identical geometries

Identical geometries return true:

SELECT SEDONA.ST_EqualsIdentical(
    ST_GeometryFromWKT('LINESTRING (0 0, 1 1)'),
    ST_GeometryFromWKT('LINESTRING (0 0, 1 1)')
)

Output:

true

Topological equality versus identity

These paths occupy the same locations, so SEDONA.ST_Equals returns true. Their coordinate sequences run in opposite directions, so SEDONA.ST_EqualsIdentical returns false.

WITH paths AS (
    SELECT
        ST_GeometryFromWKT('LINESTRING (0 0, 1 1, 2 0)') AS forward_path,
        ST_GeometryFromWKT('LINESTRING (2 0, 1 1, 0 0)') AS reverse_path
)
SELECT
    SEDONA.ST_Equals(forward_path, reverse_path) AS same_shape,
    SEDONA.ST_EqualsIdentical(forward_path, reverse_path) AS identical
FROM paths;

Output:

same_shape | identical
-----------+----------
true       | false

Geometry type and nesting

The same visible points are not identical when their geometry types and nesting differ.

SELECT SEDONA.ST_EqualsIdentical(
    ST_GeometryFromWKT('MULTIPOINT ((0 0), (4 0))'),
    ST_GeometryFromWKT(
        'GEOMETRYCOLLECTION (POINT (0 0), POINT (4 0))'
    )
) AS identical;

Output:

identical
---------
false

NULL input

The generated UDF uses Snowflake's RETURNS NULL ON NULL INPUT behavior, so a NULL operand produces NULL.

SELECT SEDONA.ST_EqualsIdentical(
    NULL,
    ST_GeometryFromWKT('POINT (1 2)')
) AS identical;

Output:

identical
---------
NULL

Practical use: geometry round-trip validation

Use ST_EqualsIdentical for deterministic change detection after serialization, storage, or an ETL rewrite. It can reveal a reversed coordinate sequence or changed geometry container even when ST_Equals reports the same shape.

The following query flags rows whose geometry representation changed:

SELECT
    record_id,
    CASE
        WHEN source_geometry IS NULL OR reloaded_geometry IS NULL THEN 'missing_geometry'
        WHEN SEDONA.ST_EqualsIdentical(source_geometry, reloaded_geometry) THEN 'unchanged'
        ELSE 'changed'
    END AS validation_result
FROM geometry_round_trip;

This predicate checks geometric content, not a byte-for-byte encoding. Compare CRS and application metadata separately when those fields are part of the validation contract. Where the input geometry types support topological equality, use SEDONA.ST_Equals in a separate comparison to distinguish representation-only changes from changed topology.