# Collection tests

Discover the different collection tests available in CQL.

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Use the summary below to quickly jump to a specific topic:

- [In test](/reference/cql/expressions/tests/collection/in): Learn how to check if an element exists in a collection.
- [Contains test](/reference/cql/expressions/tests/collection/contains): Learn how to check if a collection contains a certain element.
- [Contains all test](/reference/cql/expressions/tests/collection/contains-all): Learn how to check if a collection contains all specified elements.
- [Contains none test](/reference/cql/expressions/tests/collection/contains-none): Learn how to check if a collection has no elements in common with another.
- [Contains either test](/reference/cql/expressions/tests/collection/contains-either): Learn how to check if a collection contains one or more elements.
- [Contains neither test](/reference/cql/expressions/tests/collection/contains-neither): Learn how to check if a collection has no intersection with another.