# Schema FAQs

# What is a "Schema" in Murmurations?

See our complete definition of a Schema in the Common Terms page. Basically a Schema is a way to define the data to collect from a network, and Murmurations enables you to monitor any changes made to that data by the participants in the network.

# Are there any required fields in a Schema?

There is only one required property in a Murmurations Schema: the linked_schemas field, which is an array of strings that lists the Schema (or Schemas) against which a profile has been created.

For example, if you want to create a Profile that can be validated against both the Organizations schema (opens new window) and the Complementary Currencies schema (opens new window), your Profile document would have to include:

{
  "linked_scheams": [
    "organizations_schema-v1.0.0",
    "complementary_currencies-v2.0.0"
  ],
  // The rest of your profile...
}

# What is a profile_url?

The profile_url is the public web address where a Murmurations Profile can be accessed by the Index for indexing. Here is a profile_url for the Open Co-op: https://www.open.coop/open.json (opens new window)

When this profile_url (https://www.open.coop/open.json) is sent to the Index, its contents will be downloaded and validated by the Index. If validation is successful against all of the linked_schemas listed in the Profile, it will be recorded in the Index.

# What is a primary_url?

The primary_url field is where a Profile records its canonical web address. We can see the primary_url being used in the Open Co-op Murmurations Profile (opens new window):

{
  // ...
  "primary_url": "https://www.open.coop",
  // ...
}

The primary_url references an organization's (or individual's) primary web address. If a Profile is self-hosted on the organization's website, the primary_url will be the same domain as the profile_url, as is the case for the Open Co-op's Profile referenced in the FAQ above.

Priority should always be given to a Profile with it's primary_url being the same domain as the profile_url. In other words, a Profile that is hosted at "open.coop" and claiming "open.coop" as it's primary_url should have more weight than another Profile hosted at some other domain claiming "open.coop" as it's primary_url.