Traverses the PROPERTY_PATH path for each of the entities in VALUES. The result is all the values at the end of the traversal. This may be a single value or a list of values. PROPERTY_PATH is an expression that should resolve to a string or a list of strings. Those strings are treated as literals, i.e. property names, so no variables can be used. Only properties on the entity can be traversed. If you want to traverse to other entities use the hops function instead.


This transform function is namespaced identifiers aware.

If namespaced identifiers are enabled and the path element is not a fully qualified namespaced identifier then all properties with the path element as its identifier part will be part of the result. In practice the result is the union of all those properties.

["path", "age", ["list", {"age": 23}, {"age": 24}]]

Traverses the age field of the VALUES entities. Returns [23, 24].

["path", ["list", "order_lines", "item_name"], "_S.orders"]

This will traverse from the source entity’s orders to the order lines and then return their item names. The output is a list of product item names.

["path", "age", {"age": 24}]

Returns 24.

["path", "foo", {"bar": 123}]

Returns null.

["path", ["list", "a", "b"],
["list", {"a": {"b": 1}}, {"a": [{"b": 2}, {"b": 3}]}]]

Returns [1, 2, 3].

With namespaced identifiers enabled:

"namespaced_identifiers": true,
"namespaces": {
"identity": "foo",
"property": "bar"

["path", "foo:a", {"a": 1, "foo:a": 2, "bar:a": [3, 4]}]

Returns 2 as the path element "foo:a" is a fully qualified namespaced identifier.

["path", "a", {"a": 1, "foo:a": 2, "bar:a": [3, 4]}]

Returns [1, 2, 3, 4], i.e. the union of all the values in all the properties that have a in their identifiers part.

["path", "::a", {"a": 1, "foo:a": 2, "bar:a": [3, 4]}]

Returns 1 as "::a" uses the NI escape syntax to explicity reference the unqualified a property.

["path", ":a", {"a": 1, "foo:a": 2, "bar:a": [3, 4]}]

Returns [3, 4] as ":a" uses the NI escape syntax to explicity reference the "a" property in the current namespace "bar".