Verified operators¶

Execution tests use in-memory DuckDB tables and assert result sets, including nulls and typed timestamps. The scalar execution cases run through both the literal and parameterized helpers.

Behavior	Examples covered
Comparisons	=, <>, <, <=, >, >=
Boolean combinations	AND, OR, NOT, grouped expressions
Inclusive ranges	BETWEEN, NOT BETWEEN
Membership	IN, NOT IN; strings, numbers, booleans
Patterns	LIKE, negation, escape characters; ILIKE with evaluator configuration
Null checks	IS NULL, IS NOT NULL
Temporal values	Timestamp equality, ordering, ranges, timezone-equivalent instants
Mapped functions	Allowlisted lower and qualified function names
Arrays	Literal and bound element rendering and execution
Spatial	Intersection; native geometry, decoded WKB, GeoParquet; bound geometry/envelope/bounding box

Pattern % and _ remain wildcards. Binding a pattern prevents SQL syntax injection but does not turn a wildcard search into literal equality.

SQL three-valued logic applies: comparisons against NULL usually produce NULL, and WHERE selects only TRUE. Negation does not turn an unknown comparison into TRUE.

Use explicit null checks when null rows should be selected.

This table records verified behavior rather than asserting complete CQL conformance. Other operator behavior can be inherited from pygeofilter's SQLEvaluator; establish execution tests before relying on additional operators in a gateway.

Parser failures and HTTP responses are separate application contracts. See restricting client filters.