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Collection Spec

A _collection/spec is set of smart functions that are attached to a particular collection. Any time that collection appears in a transaction, regardless of who issues the transaction, the smart functions attached to the _collection/spec will execute.

If all of the smart functions return true, the transaction will succeed. If any of the smart functions return false, it will fail.


The most common use for collection specs to make sure a certain predicate is included in a collection. For example, the below spec, the function makes sure person/fullName is required.

"_id": ["_collection/name", "person"],
"spec": ["_fn$fullNameReq"],
"specDoc": "A person is required to have a fullName."
"_id": "_fn$fullNameReq",
"name": "fullNameReq",
"code": "(boolean (get (query (str \"{\\\"select\\\": [\\\"*\\\"], \\\"from\\\":\" (?sid) \"}\")) \"person/fullName\"))"