collection

Define a Collection schema, including index and unique and check constraint fields.

Syntax

[@alias(<aliasId>]
collection <collName> {
  [<fieldName>: <field definition> . . .]
  [migrations <migrations block>]
  [history_days <history days>]
  [document_ttls <Boolean | Null>]
  [ttl_days <time to live days>]
  [index <index name> <index config block> . . .]
  [unique <unique constraint fields> . . .]
  [check <name> <predicateBody> . . .]
  [compute <name> [: <type>] <anonymousFunction> . . .]
}

Name

collName String Required

Name of the collection. The collName must match the following regular expression but can’t be a single underscore or reserved word: [a-zA-Z_]+[a-zA-Z0-9_]*. A collName should be singular and PascalCased.

Properties

Parameter Type Required Description

<fieldName>

String

Document field names and definitions. See Field definitions.

migrations

String

See Migrations block.

history_days

Int

Number of days of document history to retain for all documents in the collection. See Temporality.

document_ttls

Boolean | Null

If true, you can write to the ttl field of the collection’s documents.

If the collection schema contains field definitions, document_ttls defaults to false. Otherwise, document_ttls defaults to true.

document_ttls does not stop ttl-related deletions or affect ttl values set by the collection schema’s ttl_days field.

See Enable or disable ttl writes.

ttl_days

Int

Number of days that documents in the collection should be retained. See Temporality.

If the collection schema’s document_ttls field is false, Fauna ignores this field.

index

String

See collection.index.

unique

String

See collection.unique.

check

String

See collection.check.

compute

String

See collection.compute.

Annotations

aliasId String or Identifier

The optional @alias annotation defines a second identifier for the collection. The aliasId can be a String, "Foo", or an identifier, Foo.

Collection aliases are useful when migrating from FQL v4 and you have collection names that violate the FQL v10 naming rules. See reserved schema names.

Examples

collection Product {
  name: String?
  description: String?
  price: Double = 0.00
  quantity: Int = 0
  store: Ref<Store>?
  backorderLimit: Int?
  backordered: Boolean?
  categories: Array<String>?
  creationTime: Time = Time.now()
  creationTimeEpoch: Int?
  typeConflicts: { *: Any }?

  *: Any

  migrations {
    add .typeConflicts
    add .quantity
    backfill .quantity = 0
    drop .internalDesc
    move_conflicts .typeConflicts
    move .desc -> .description
    split .creationTime -> .creationTime, .creationTimeEpoch
  }

  unique [.name, .description, mva(.categories)]

  index byName {
    terms [.name]
    values [desc(.quantity), desc(mva(.categories))]
  }

  check posQuantity ((doc) => doc.quantity >= 0)
  compute InventoryValue: Number = (.quantity * .price)

  history_days 3
  document_ttls true
  ttl_days 5
}

See also

Field definitions
Migrations block
collection.index
collection.unique
collection.check
collection.compute

Is this article helpful? 

Tell Fauna how the article can be improved:
 Visit Fauna's forums or email docs@fauna.com

Thank you for your feedback!