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document.replace()

Learn: Documents

Replace all fields in a collection document.

Signature

replace(data: { ttl: Time | Null, data: Null, *: Any }) => <Document>

Description

Replaces all fields in an collection document with fields from a provided data object. Fields not present in the data object, excluding the id, coll, ts, and data metadata fields, are removed.

Metadata fields

You can’t use this method to replace the following metadata fields:

  • id

  • coll

  • ts

  • data

Reserved fields

You can’t use this method to insert or edit the following metadata fields:

  • id

  • coll

  • ts

  • data

Parameters

Parameter Type Required Description

data

Object

true

Fields for the collection document. Fields not present in the object, excluding the id, coll, ts, and data metadata fields, are removed.

The object can’t include the following metadata fields:

  • id

  • coll

  • ts

  • data

Return value

Type Description

<Document>

Collection document with replaced fields.

A document’s data type is taken from its collection’s name. For example, Product for a document in the Product collection. See Document type.

Examples

Basic

Given the following document:

{
  id: "777",
  coll: Product,
  ts: Time("2099-04-10T16:50:12.850Z"),
  name: "limes",
  description: "Conventional, 16 oz bag",
  price: 2_99,
  stock: 30,
  category: Category("789")
}

Call replace() with a replacement document object:

Product.byId("777")?.replace({
  name: "limes",
  description: "2 ct",
  price: 99,
  stock: 50,
  category: Category.byId("789")
})
{
  id: "777",
  coll: Product,
  ts: Time("2099-04-10T17:54:37.670Z"),
  name: "limes",
  description: "2 ct",
  price: 99,
  stock: 50,
  category: Category("789")
}

Default values

A field definition can set a default field value for documents in a collection:

collection Customer {
  // `name` accepts `String` and `Null` values.
  // If missing, defaults to `unknown`.
  name: String? = "unknown"
  email: String
}

If you don’t provide a value during document replacement, the document uses the default value:

// Replaces a `Customer` document.
Customer.byId("111")?.replace({
  // The `name` field is missing.
  email: "john.doe@example.com"
})
{
  id: "111",
  coll: Customer,
  ts: Time("2099-02-19T14:53:53.940Z"),
  cart: Order("413002506150347264"),
  orders: "hdW...",
  email: "john.doe@example.com",
  // `name` defaulted to `unknown`.
  name: "unknown"
}

If you provide an explicit null value, the field is null. Fields with null values aren’t stored or returned.

Customer.byId("111")?.replace({
  // `name` is an explicit `null`.
  name: null,
  email: "jane.doe@example.com"
})
{
  id: "111",
  coll: Customer,
  ts: Time("2099-02-19T14:53:53.940Z"),
  cart: Order("413002506150347264"),
  orders: "hdW...",
  // `name` is not stored or returned.
  email: "jane.doe@example.com"
}

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