COUNT - Query language in Cosmos DB (in Azure and Fabric)

The COUNT function returns the count of the values in the expression.

Syntax

COUNT(<scalar_expr>)

Arguments

	Description
scalar_expr	A scalar expression to count.

Return types

Returns a numeric scalar value.

Examples

This section contains examples of how to use this query language construct.

Consider this sample set of documents within the Products collection for these examples.

[
  {
    "name": "Kameni Adult Bike Helmet",
    "detailCategory": "gear-cycle-helmets"
  },
  {
    "name": "Rockmak Full Face Helmet",
    "detailCategory": "gear-cycle-helmets"
  },
  {
    "name": "Barea Skateboard Helmet",
    "detailCategory": "gear-cycle-helmets"
  },
  {
    "name": "Cranix Full Face Helmet",
    "detailCategory": "gear-cycle-helmets"
  },
  {
    "name": "Furano Adult Bike Helmet",
    "detailCategory": "gear-cycle-helmets"
  },
  {
    "name": "Prigla Adult Bike Helmet",
    "detailCategory": "gear-cycle-helmets"
  },
  {
    "name": "Menitos Skateboard Helmet",
    "detailCategory": "gear-cycle-helmets"
  },
  {
    "name": "Knimer Adult Bike Helmet",
    "detailCategory": "gear-cycle-helmets"
  },
  {
    "name": "Cranix Bike Helmet",
    "detailCategory": "gear-cycle-helmets"
  },
  {
    "name": "Jeropa Adult Bike Helmet",
    "detailCategory": "gear-cycle-helmets"
  }
]

Count using a scalar value and an expression

In this example, COUNT is used with a scalar and an expression. Both return 1.

SELECT VALUE {
  countScalar: COUNT(1),
  countExpression: COUNT(2 + 3)
}

[
  {
    "countScalar": 1,
    "countExpression": 1
  }
]

Count occurrences of a field

In this example, the function counts the number of times the name field occurs in filtered data.

SELECT VALUE
  COUNT(p.name)
FROM
  products p
WHERE
  p.detailCategory = "gear-cycle-helmets"

[
  10
]

Count all items

In this example, the function is used to count every item within a container that matches the filter.

SELECT VALUE
  COUNT(1)
FROM
  products p
WHERE
  p.detailCategory = "gear-cycle-helmets"

[
  10
]

Remarks

• This function benefits from the use of a range index for any properties in the query's filter. For more information, see range indexes.