PQL COUNT()

The Count() query returns the number of record IDs / keys returned by a row call. Note that this includes the Distinct() call – see the example below.

Call Definition

Count(ROW_CALL)

Mandatory Arguments

• ROW_CALL : the row call to be counted

Optional Arguments

Returns

• a single unsigned integer that is the count of record IDs / keys returned by ROW_CALL

Examples

Data:

Index: customer (non keyed)

 _id | age (Int) | has_purchased (Set) | last_purchase (Timestamp)
-----+-----------+---------------------+--------------------------
 0   | 23        | ["brand1","brand2"] | 2021-01-05T08:30:00Z
 1   | 31        | ["brand1","brand3"] | 2020-09-12T12:30:00Z
 2   | 28        | ["brand1","brand3"] | 2021-08-06T16:15:00Z
 3   | 19        | []                  | null
 4   | 25        | ["brand1","brand4"] | 2021-10-01T20:45:00Z
 5   | 40        | ["brand4"]          | 2022-01-13T11:00:00Z

Example 1

How many records (customers) do we have in the index?

Query

[customer]Count(All())

Tabular Response

 count
-------
 6

HTTP Response

{
  "results": [
    6
  ]
}

Explanation

All() returns a list of all the record IDs in the index. There are six records so Count() returns 6.

Example 2

How many customers have purchased from brand1?

Query

[customer]Count(
  Row(has_purchased = brand1)
)

Tabular Response

 count
-------
 4

HTTP Response

{
  "results": [
    4
  ]
}

Explanation

Row(has_purchased = brand1) returns [0,1,2,4]. There are four records so Count() returns 4.

Example 3

How many distinct brands have been purchased from?

Query

[customer]Count(
  Distinct(field=has_purchased)
)

Tabular Response

 count
-------
 4

HTTP Response

{
  "results": [
    4
  ]
}

Explanation

Distinct(field=has_purchased) returns brand1, brand2, brand3, and brand4. Since there are four values we get a count of 4 returned.