Map Functions Reference

Map Functions

Name Description
MAP Constructs a map value from a series of key-value pairs
MAP_GET Returns the value in a map given a specified key
MAP_SET Returns a copy of a map with a series of updated keys
MAP_REMOVE Returns a copy of a map with a series of keys removed
MAP_MERGE Merges a series of maps together.
CURRENT_CONTEXT Returns the current context as a map.
MAP_KEYS Returns an array of all keys in a map.
MAP_VALUES Returns an array of all values in a map.
MAP_ENTRIES Returns an array of key-value pairs of a map.

MAP

Syntax:

map(key: STRING, value: ANY, ...) -> MAP

Description:

Constructs a map from a series of key-value pairs.

MAP_GET

Syntax:

map_get(map: ANY, key: STRING) -> ANY

Description:

Returns the value in a map given a specified key. Returns an ABSENT value if the key does not exist in the map, or if the map argument is not a MAP.

Node.js
const result = await db.pipeline()
  .collection("books")
  .select(
    field("awards").mapGet("pulitzer").as("hasPulitzerAward")
  )
  .execute();
test.firestore.js

Web

const result = await execute(db.pipeline()
  .collection("books")
  .select(
    field("awards").mapGet("pulitzer").as("hasPulitzerAward")
  )
);
test.firestore.js
Swift
let result = try await db.pipeline()
  .collection("books")
  .select([
    Field("awards").mapGet("pulitzer").as("hasPulitzerAward")
  ])
  .execute()
PipelineSnippets.swift
Kotlin
Android
val result = db.pipeline()
    .collection("books")
    .select(
        field("awards").mapGet("pulitzer").alias("hasPulitzerAward")
    )
    .execute()
DocSnippets.kt
Java
Android
Task<Pipeline.Snapshot> result = db.pipeline()
    .collection("books")
    .select(
        field("awards").mapGet("pulitzer").alias("hasPulitzerAward")
    )
    .execute();
DocSnippets.java
Python
from google.cloud.firestore_v1.pipeline_expressions import Field

result = (
    client.pipeline()
    .collection("books")
    .select(Field.of("awards").map_get("pulitzer").as_("hasPulitzerAward"))
    .execute()
)
firestore_pipelines.py
Java
Pipeline.Snapshot result =
    firestore
        .pipeline()
        .collection("books")
        .select(mapGet(field("awards"), "pulitzer").as("hasPulitzerAward"))
        .execute()
        .get();
PipelineSnippets.java

MAP_SET

Syntax:

map_set(map: MAP, key: STRING, value: ANY, ...) -> MAP

Description:

Returns a copy of the map value with its contents updated by a series of key-value pairs.

If the given resolves to an absent value, the associated key is removed from the map.

If the map argument is not a MAP, returns an absent value.

MAP_REMOVE

Syntax:

map_remove(map: MAP, key: STRING...) -> MAP

Description:

Returns a copy of the map value with a series of keys removed.

MAP_MERGE

Syntax:

map_merge(maps: MAP...) -> MAP

Merges the contents of 2 or more maps. If multiple maps have conflicting values, the last value is used.

CURRENT_CONTEXT

Syntax:

current_context() -> MAP

Returns a map consisting of all available fields in the current point of execution.

MAP_KEYS

Syntax:

map_keys(map: MAP) -> ARRAY<STRING>

Description:

Returns an array containing all keys of the map value.

MAP_VALUES

Syntax:

map_values(map: MAP) -> ARRAY<ANY>

Description:

Returns an array containing all values of the map value.

MAP_ENTRIES

Syntax:

map_entries(map: MAP) -> ARRAY<MAP>

Description:

Returns an array containing all key-value pairs in the map value.

Each key-value pair will be in the form of a map with two entries, k and v.

Examples:

map map_entries(map)
{} []
{"foo" : 2L} [{"k": "foo", "v" : 2L}]
{"foo" : "bar", "bar" : "foo"} [{"k": "foo", "v" : "bar" }, {"k" : "bar", "v": "foo"}]

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