Array functions

Array Functions

Name Description
ARRAY Returns an ARRAY containing one element for each input argument
ARRAY_CONCAT Concatenates multiple arrays into a single ARRAY
ARRAY_CONTAINS Returns TRUE if a given ARRAY contains a particular value
ARRAY_CONTAINS_ALL Returns TRUE if all values are present in the ARRAY
ARRAY_CONTAINS_ANY Returns TRUE if any of the values are present in the ARRAY
ARRAY_GET Returns the element at a given index in an ARRAY
ARRAY_LENGTH Returns the number of elements in an ARRAY
ARRAY_REVERSE Reverses the order of elements in an ARRAY
SUM Returns the sum of all NUMERIC values in an ARRAY.
JOIN Produces a concatenation of the elements in an ARRAY as a STRING value.

ARRAY

Syntax:

array(values: ANY...) -> ARRAY

Description:

Constructs an array from the given elements.

  • If an argument does not exist, it is replaced with NULL in the resulting array.

Examples:

values array(values)
() []
(1, 2, 3) [1, 2, 3]
("a", 1, true) ["a", 1, true]
(1, null) [1, null]
(1, [2, 3]) [1, [2, 3]]

ARRAY_CONCAT

Syntax:

array_concat(arrays: ARRAY...) -> ARRAY

Description:

Concatenates two or more arrays into a single ARRAY.

Examples:

arrays array_concat(arrays)
([1, 2], [3, 4]) [1, 2, 3, 4]
(["a", "b"], ["c"]) ["a", "b", "c"]
([1], [2], [3]) [1, 2, 3]
([], [1, 2]) [1, 2]
Node.js
const result = await db.pipeline()
  .collection("books")
  .select(field("genre").arrayConcat([field("subGenre")]).as("allGenres"))
  .execute();
test.firestore.js
Swift
let result = try await db.pipeline()
  .collection("books")
  .select([Field("genre").arrayConcat([Field("subGenre")]).as("allGenres")])
  .execute()
PipelineSnippets.swift

Kotlin

val result = db.pipeline()
    .collection("books")
    .select(field("genre").arrayConcat(field("subGenre")).alias("allGenres"))
    .execute()
DocSnippets.kt

Java

Task<Pipeline.Snapshot> result = db.pipeline()
    .collection("books")
    .select(field("genre").arrayConcat(field("subGenre")).alias("allGenres"))
    .execute();
DocSnippets.java
Python
from google.cloud.firestore_v1.pipeline_expressions import Field

result = (
    client.pipeline()
    .collection("books")
    .select(Field.of("genre").array_concat(Field.of("subGenre")).as_("allGenres"))
    .execute()
)
firestore_pipelines.py
Java
Pipeline.Snapshot result =
    firestore
        .pipeline()
        .collection("books")
        .select(arrayConcat(field("genre"), field("subGenre")).as("allGenres"))
        .execute()
        .get();
PipelineSnippets.java

ARRAY_CONTAINS

Syntax:

array_contains(array: ARRAY, value: ANY) -> BOOLEAN

Description:

Returns TRUE if value is found in the array, and FALSE otherwise.

Examples:

array value array_contains(array, value)
[1, 2, 3] 2 true
[[1, 2], [3]] [1, 2] true
[1, null] null true
"abc" ANY error
Node.js
const result = await db.pipeline()
  .collection("books")
  .select(field("genre").arrayContains(constant("mystery")).as("isMystery"))
  .execute();
test.firestore.js

Web

const result = await execute(db.pipeline()
  .collection("books")
  .select(field("genre").arrayContains(constant("mystery")).as("isMystery"))
);
test.firestore.js
Swift
let result = try await db.pipeline()
  .collection("books")
  .select([Field("genre").arrayContains(Constant("mystery")).as("isMystery")])
  .execute()
PipelineSnippets.swift

Kotlin

val result = db.pipeline()
    .collection("books")
    .select(field("genre").arrayContains("mystery").alias("isMystery"))
    .execute()
DocSnippets.kt

Java

Task<Pipeline.Snapshot> result = db.pipeline()
    .collection("books")
    .select(field("genre").arrayContains("mystery").alias("isMystery"))
    .execute();
DocSnippets.java
Python
from google.cloud.firestore_v1.pipeline_expressions import Field

result = (
    client.pipeline()
    .collection("books")
    .select(Field.of("genre").array_contains("mystery").as_("isMystery"))
    .execute()
)
firestore_pipelines.py
Java
Pipeline.Snapshot result =
    firestore
        .pipeline()
        .collection("books")
        .select(arrayContains(field("genre"), "mystery").as("isMystery"))
        .execute()
        .get();
PipelineSnippets.java

ARRAY_CONTAINS_ALL

Syntax:

array_contains_all(array: ARRAY, search_values: ARRAY) -> BOOLEAN

Description:

Returns TRUE if all search_values are found in the array, and FALSE otherwise.

Examples:

array search_values array_contains_all(array, search_values)
[1, 2, 3] [1, 2] true
[1, 2, 3] [1, 4] false
[1, null] [null] true
[NaN] [NaN] true
[] [] true
[1, 2, 3] [] true
Node.js
const result = await db.pipeline()
  .collection("books")
  .select(
    field("genre")
      .arrayContainsAll([constant("fantasy"), constant("adventure")])
      .as("isFantasyAdventure")
  )
  .execute();
test.firestore.js

Web

const result = await execute(db.pipeline()
  .collection("books")
  .select(
    field("genre")
      .arrayContainsAll([constant("fantasy"), constant("adventure")])
      .as("isFantasyAdventure")
  )
);
test.firestore.js
Swift
let result = try await db.pipeline()
  .collection("books")
  .select([
    Field("genre")
      .arrayContainsAll([Constant("fantasy"), Constant("adventure")])
      .as("isFantasyAdventure")
  ])
  .execute()
PipelineSnippets.swift

Kotlin

val result = db.pipeline()
    .collection("books")
    .select(
        field("genre")
            .arrayContainsAll(listOf("fantasy", "adventure"))
            .alias("isFantasyAdventure")
    )
    .execute()
DocSnippets.kt

Java

Task<Pipeline.Snapshot> result = db.pipeline()
    .collection("books")
    .select(
        field("genre")
            .arrayContainsAll(Arrays.asList("fantasy", "adventure"))
            .alias("isFantasyAdventure")
    )
    .execute();
DocSnippets.java
Python
from google.cloud.firestore_v1.pipeline_expressions import Field

result = (
    client.pipeline()
    .collection("books")
    .select(
        Field.of("genre")
        .array_contains_all(["fantasy", "adventure"])
        .as_("isFantasyAdventure")
    )
    .execute()
)
firestore_pipelines.py
Java
Pipeline.Snapshot result =
    firestore
        .pipeline()
        .collection("books")
        .select(
            arrayContainsAll(field("genre"), Arrays.asList("fantasy", "adventure"))
                .as("isFantasyAdventure"))
        .execute()
        .get();
PipelineSnippets.java

ARRAY_CONTAINS_ANY

Syntax:

array_contains_any(array: ARRAY, search_values: ARRAY) -> BOOLEAN

Description:

Returns TRUE if any of the search_values are found in the array, and FALSE otherwise.

Examples:

array search_values array_contains_any(array, search_values)
[1, 2, 3] [4, 1] true
[1, 2, 3] [4, 5] false
[1, 2, null] [null] true
Node.js
const result = await db.pipeline()
  .collection("books")
  .select(
    field("genre")
      .arrayContainsAny([constant("fantasy"), constant("nonfiction")])
      .as("isMysteryOrFantasy")
  )
  .execute();
test.firestore.js

Web

const result = await execute(db.pipeline()
  .collection("books")
  .select(
    field("genre")
      .arrayContainsAny([constant("fantasy"), constant("nonfiction")])
      .as("isMysteryOrFantasy")
  )
);
test.firestore.js
Swift
let result = try await db.pipeline()
  .collection("books")
  .select([
    Field("genre")
      .arrayContainsAny([Constant("fantasy"), Constant("nonfiction")])
      .as("isMysteryOrFantasy")
  ])
  .execute()
PipelineSnippets.swift

Kotlin

val result = db.pipeline()
    .collection("books")
    .select(
        field("genre")
            .arrayContainsAny(listOf("fantasy", "nonfiction"))
            .alias("isMysteryOrFantasy")
    )
    .execute()
DocSnippets.kt

Java

Task<Pipeline.Snapshot> result = db.pipeline()
    .collection("books")
    .select(
        field("genre")
            .arrayContainsAny(Arrays.asList("fantasy", "nonfiction"))
            .alias("isMysteryOrFantasy")
    )
    .execute();
DocSnippets.java
Python
from google.cloud.firestore_v1.pipeline_expressions import Field

result = (
    client.pipeline()
    .collection("books")
    .select(
        Field.of("genre")
        .array_contains_any(["fantasy", "nonfiction"])
        .as_("isMysteryOrFantasy")
    )
    .execute()
)
firestore_pipelines.py
Java
Pipeline.Snapshot result =
    firestore
        .pipeline()
        .collection("books")
        .select(
            arrayContainsAny(field("genre"), Arrays.asList("fantasy", "nonfiction"))
                .as("isMysteryOrFantasy"))
        .execute()
        .get();
PipelineSnippets.java

ARRAY_GET

Syntax:

array_get(array: ARRAY, index: INT64) -> ANY

Description:

Returns the element at the 0-based index in array.

  • If index is negative, elements are accessed from the end of array, where -1 is the last element.
  • If array is not of type ARRAY, the function returns an absent value.
  • If index is out of bounds, the function returns an absent value.
  • If index is not of type INT64, the function returns an error.

Examples:

array index array_get(array, index)
[1, 2, 3] 0 1
[1, 2, 3] -1 3
[1, 2, 3] 3 absent
[1, 2, 3] -4 absent
"abc" 0 absent
null 0 absent
Array "a" error
Array 2.0 error

ARRAY_LENGTH

Syntax:

array_length(array: ARRAY) -> INT64

Description:

Returns the number of elements in array.

Examples:

array array_length(array)
[1, 2, 3] 3
[] 0
[1, 1, 1] 3
[1, null] 2
Node.js
const result = await db.pipeline()
  .collection("books")
  .select(field("genre").arrayLength().as("genreCount"))
  .execute();
test.firestore.js

Web

const result = await execute(db.pipeline()
  .collection("books")
  .select(field("genre").arrayLength().as("genreCount"))
);
test.firestore.js
Swift
let result = try await db.pipeline()
  .collection("books")
  .select([Field("genre").arrayLength().as("genreCount")])
  .execute()
PipelineSnippets.swift

Kotlin

val result = db.pipeline()
    .collection("books")
    .select(field("genre").arrayLength().alias("genreCount"))
    .execute()
DocSnippets.kt

Java

Task<Pipeline.Snapshot> result = db.pipeline()
    .collection("books")
    .select(field("genre").arrayLength().alias("genreCount"))
    .execute();
DocSnippets.java
Python
from google.cloud.firestore_v1.pipeline_expressions import Field

result = (
    client.pipeline()
    .collection("books")
    .select(Field.of("genre").array_length().as_("genreCount"))
    .execute()
)
firestore_pipelines.py
Java
Pipeline.Snapshot result =
    firestore
        .pipeline()
        .collection("books")
        .select(arrayLength(field("genre")).as("genreCount"))
        .execute()
        .get();
PipelineSnippets.java

ARRAY_REVERSE

Syntax:

array_reverse(array: ARRAY) -> ARRAY

Description:

Reverses the given array.

Examples:

array array_reverse(array)
[1, 2, 3] [3, 2, 1]
["a", "b"] ["b", "a"]
[1, 2, 2, 3] [3, 2, 2, 1]
Node.js
const result = await db.pipeline()
  .collection("books")
  .select(arrayReverse(field("genre")).as("reversedGenres"))
  .execute();
test.firestore.js

Web

const result = await execute(db.pipeline()
  .collection("books")
  .select(field("genre").arrayReverse().as("reversedGenres"))
);
test.firestore.js
Swift
let result = try await db.pipeline()
  .collection("books")
  .select([Field("genre").arrayReverse().as("reversedGenres")])
  .execute()
PipelineSnippets.swift

Kotlin

val result = db.pipeline()
    .collection("books")
    .select(field("genre").arrayReverse().alias("reversedGenres"))
    .execute()
DocSnippets.kt
 
    
Java

Task<Pipeline.Snapshot> result = db.pipeline()
    .collection("books")
    .select(field("genre").arrayReverse().alias("reversedGenres"))
    .execute();
DocSnippets.java
Python
from google.cloud.firestore_v1.pipeline_expressions import Field

result = (
    client.pipeline()
    .collection("books")
    .select(Field.of("genre").array_reverse().as_("reversedGenres"))
    .execute()
)
firestore_pipelines.py
Java
Pipeline.Snapshot result =
    firestore
        .pipeline()
        .collection("books")
        .select(arrayReverse(field("genre")).as("reversedGenres"))
        .execute()
        .get();
PipelineSnippets.java

SUM

Syntax:

sum(array: ARRAY) -> INT64 | FLOAT64

Description:

Returns the sum of all NUMERIC values in an ARRAY.

  • Non-numeric values in the array are ignored.
  • If any numeric value in the array is NaN, the function returns NaN.
  • The return type is determined by the widest numeric type in the array: INT64 < FLOAT64.
  • If 64-bit integer overflow occurs before any floating point value is summed, an error is returned. If floating point values are summed, overflow will result in +/- infinity.
  • If the array contains no numeric values at all, the function returns NULL.

Examples:

array sum(array)
[1, 2, 3] 6L
[1L, 2L, 3L] 6L
[2000000000, 2000000000] 4000000000L
[10, 20.5] 30.5
[1, "a", 2] 3L
[INT64.MAX_VALUE, 1] error
[INT64.MAX_VALUE, 1, -1.0] error
[INT64.MAX_VALUE, 1.0] 9.223372036854776e+18

JOIN

Syntax:

join[T <: STRING | BYTES](array: ARRAY<T>, delimiter: T) -> STRING
join[T <: STRING | BYTES](array: ARRAY<T>, delimiter: T, null_text: T) -> STRING

Description:

Returns a concatenation of the elements in array as a STRING. The array can be of STRING or BYTES data types.

  • All elements in array, delimiter, and null_text must be of the same type; they must all be STRINGs or all be BYTES.
  • If null_text is provided, any NULL values in array are replaced with null_text.
  • If null_text is not provided, NULL values in array are omitted from the result.

Examples:

When null_text is not provided:

array delimiter join(array, delimiter)
["a", "b", "c"] "," "a,b,c"
["a", null, "c"] "," "a,c"
[b'a', b'b', b'c'] b',' b'a,b,c'
["a", b'c'] "," error
["a", "c"] b',' error
[b'a', b'c'] "," error

When null_text is provided:

array delimiter null_text join(array, delimiter, null_text)
["a", null, "c"] "," "MISSING" "a,MISSING,c"
[b'a', null, b'c'] b',' b'NULL' b'a,NULL,c'
[null, "b", null] "," "MISSING" "MISSING,b,MISSING"
[b'a', null, null] b',' b'NULL' b'a,NULL,NULL'
["a", null] "," b'N' error
[b'a', null] b',' "N" error