Riferimento per le funzioni di confronto
Funzioni di confronto
| Nome | Descrizione |
EQUAL
|
Confronto di uguaglianza |
GREATER_THAN
|
Confronto maggiore di |
GREATER_THAN_OR_EQUAL
|
Confronto maggiore o uguale a |
LESS_THAN
|
Confronto con il segno "minore di" |
LESS_THAN_OR_EQUAL
|
Confronto minore o uguale |
NOT_EQUAL
|
Confronto diverso da |
CMP
|
Confronto generale |
EQUAL
Sintassi:
equal(x: ANY, y: ANY) -> BOOLEAN
Esempi:
x |
y |
equal(x, y) |
|---|---|---|
| 1L | 1L | TRUE |
| 1.0 | 1L | TRUE |
| -1.0 | 1L | FALSE |
| NaN | NaN | TRUE |
NULL |
NULL |
TRUE |
NULL |
ABSENT |
FALSE |
Descrizione:
Restituisce TRUE se x e y sono uguali, altrimenti restituisce FALSE.
Node.js
const result = await db.pipeline() .collection("books") .select(field("rating").equal(5).as("hasPerfectRating")) .execute();
Web
const result = await execute(db.pipeline() .collection("books") .select(field("rating").equal(5).as("hasPerfectRating")) );
Swift
let result = try await db.pipeline() .collection("books") .select([Field("rating").equal(5).as("hasPerfectRating")]) .execute()
Kotlin
Android
val result = db.pipeline() .collection("books") .select(field("rating").equal(5).alias("hasPerfectRating")) .execute()
Java
Android
Task<Pipeline.Snapshot> result = db.pipeline() .collection("books") .select(field("rating").equal(5).alias("hasPerfectRating")) .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client.pipeline() .collection("books") .select(Field.of("rating").equal(5).as_("hasPerfectRating")) .execute() )
Java
Pipeline.Snapshot result = firestore .pipeline() .collection("books") .select(equal(field("rating"), 5).as("hasPerfectRating")) .execute() .get();
MAGGIORE_DI
Sintassi:
greater_than(x: ANY, y: ANY) -> BOOLEAN
Descrizione:
Restituisce TRUE se x è maggiore di y, altrimenti restituisce FALSE.
Se x e y non sono confrontabili, restituisce FALSE.
Esempi:
x |
y |
greater_than(x, y) |
|---|---|---|
| 1L | 0.0 | TRUE |
| 1L | 1L | FALSE |
| 1L | 2L | FALSE |
| "foo" | 0L | FALSE |
| 0L | "foo" | FALSE |
| NaN | 0L | FALSE |
| 0L | NaN | FALSE |
NULL |
NULL |
FALSE |
Node.js
const result = await db.pipeline() .collection("books") .select(field("rating").greaterThan(4).as("hasHighRating")) .execute();
Web
const result = await execute(db.pipeline() .collection("books") .select(field("rating").greaterThan(4).as("hasHighRating")) );
Swift
let result = try await db.pipeline() .collection("books") .select([Field("rating").greaterThan(4).as("hasHighRating")]) .execute()
Kotlin
Android
val result = db.pipeline() .collection("books") .select(field("rating").greaterThan(4).alias("hasHighRating")) .execute()
Java
Android
Task<Pipeline.Snapshot> result = db.pipeline() .collection("books") .select(field("rating").greaterThan(4).alias("hasHighRating")) .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client.pipeline() .collection("books") .select(Field.of("rating").greater_than(4).as_("hasHighRating")) .execute() )
Java
Pipeline.Snapshot result = firestore .pipeline() .collection("books") .select(greaterThan(field("rating"), 4).as("hasHighRating")) .execute() .get();
MAGGIORE_UGUALE
Sintassi:
greater_than_or_equal(x: ANY, y: ANY) -> BOOLEAN
Descrizione:
Restituisce TRUE se x è maggiore o uguale a y, altrimenti restituisce FALSE.
Se x e y non sono confrontabili, restituisce FALSE.
Esempi:
x |
y |
greater_than_or_equal(x, y) |
|---|---|---|
| 1L | 0.0 | TRUE |
| 1L | 1L | TRUE |
| 1L | 2L | FALSE |
| "foo" | 0L | FALSE |
| 0L | "foo" | FALSE |
| NaN | 0L | FALSE |
| 0L | NaN | FALSE |
NULL |
NULL |
TRUE |
Node.js
const result = await db.pipeline() .collection("books") .select(field("published").greaterThanOrEqual(1900).as("publishedIn20thCentury")) .execute();
Web
const result = await execute(db.pipeline() .collection("books") .select(field("published").greaterThanOrEqual(1900).as("publishedIn20thCentury")) );
Swift
let result = try await db.pipeline() .collection("books") .select([Field("published").greaterThanOrEqual(1900).as("publishedIn20thCentury")]) .execute()
Kotlin
Android
val result = db.pipeline() .collection("books") .select(field("published").greaterThanOrEqual(1900).alias("publishedIn20thCentury")) .execute()
Java
Android
Task<Pipeline.Snapshot> result = db.pipeline() .collection("books") .select(field("published").greaterThanOrEqual(1900).alias("publishedIn20thCentury")) .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client.pipeline() .collection("books") .select( Field.of("published") .greater_than_or_equal(1900) .as_("publishedIn20thCentury") ) .execute() )
Java
Pipeline.Snapshot result = firestore .pipeline() .collection("books") .select(greaterThanOrEqual(field("published"), 1900).as("publishedIn20thCentury")) .execute() .get();
LESS_THAN
Sintassi:
less_than(x: ANY, y: ANY) -> BOOLEAN
Descrizione:
Restituisce TRUE se x è minore di y, altrimenti restituisce FALSE.
Se x e y non sono confrontabili, restituisce FALSE.
Esempi:
x |
y |
less_than(x, y) |
|---|---|---|
| 1L | 0.0 | FALSE |
| 1L | 1L | FALSE |
| 1L | 2L | TRUE |
| "foo" | 0L | FALSE |
| 0L | "foo" | FALSE |
| NaN | 0L | FALSE |
| 0L | NaN | FALSE |
NULL |
NULL |
FALSE |
Node.js
const result = await db.pipeline() .collection("books") .select(field("published").lessThan(1923).as("isPublicDomainProbably")) .execute();
Web
const result = await execute(db.pipeline() .collection("books") .select(field("published").lessThan(1923).as("isPublicDomainProbably")) );
Swift
let result = try await db.pipeline() .collection("books") .select([Field("published").lessThan(1923).as("isPublicDomainProbably")]) .execute()
Kotlin
Android
val result = db.pipeline() .collection("books") .select(field("published").lessThan(1923).alias("isPublicDomainProbably")) .execute()
Java
Android
Task<Pipeline.Snapshot> result = db.pipeline() .collection("books") .select(field("published").lessThan(1923).alias("isPublicDomainProbably")) .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client.pipeline() .collection("books") .select(Field.of("published").less_than(1923).as_("isPublicDomainProbably")) .execute() )
Java
Pipeline.Snapshot result = firestore .pipeline() .collection("books") .select(lessThan(field("published"), 1923).as("isPublicDomainProbably")) .execute() .get();
LESS_THAN_OR_EQUAL
Sintassi:
less_than_or_equal(x: ANY, y: ANY) -> BOOLEAN
Descrizione:
Restituisce TRUE se x è minore o uguale a y, altrimenti restituisce FALSE.
Se x e y non sono confrontabili, restituisce FALSE.
Esempi:
x |
y |
less_than(x, y) |
|---|---|---|
| 1L | 0.0 | FALSE |
| 1L | 1L | TRUE |
| 1L | 2L | TRUE |
| "foo" | 0L | FALSE |
| 0L | "foo" | FALSE |
| NaN | 0L | FALSE |
| 0L | NaN | FALSE |
NULL |
NULL |
TRUE |
Node.js
const result = await db.pipeline() .collection("books") .select(field("rating").lessThanOrEqual(2).as("hasBadRating")) .execute();
Web
const result = await execute(db.pipeline() .collection("books") .select(field("rating").lessThanOrEqual(2).as("hasBadRating")) );
Swift
let result = try await db.pipeline() .collection("books") .select([Field("rating").lessThanOrEqual(2).as("hasBadRating")]) .execute()
Kotlin
Android
val result = db.pipeline() .collection("books") .select(field("rating").lessThanOrEqual(2).alias("hasBadRating")) .execute()
Java
Android
Task<Pipeline.Snapshot> result = db.pipeline() .collection("books") .select(field("rating").lessThanOrEqual(2).alias("hasBadRating")) .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client.pipeline() .collection("books") .select(Field.of("rating").less_than_or_equal(2).as_("hasBadRating")) .execute() )
Java
Pipeline.Snapshot result = firestore .pipeline() .collection("books") .select(lessThanOrEqual(field("rating"), 2).as("hasBadRating")) .execute() .get();
NOT_EQUAL
Sintassi:
not_equal(x: ANY, y: ANY) -> BOOLEAN
Descrizione:
Restituisce TRUE se x non è uguale a y, altrimenti restituisce FALSE.
Esempi:
x |
y |
not_equal(x, y) |
|---|---|---|
| 1L | 1L | FALSE |
| 1.0 | 1L | FALSE |
| -1.0 | 1L | TRUE |
| NaN | 0L | TRUE |
| NaN | NaN | FALSE |
NULL |
NULL |
FALSE |
NULL |
ABSENT |
TRUE |
Node.js
const result = await db.pipeline() .collection("books") .select(field("title").notEqual("1984").as("not1984")) .execute();
Web
const result = await execute(db.pipeline() .collection("books") .select(field("title").notEqual("1984").as("not1984")) );
Swift
let result = try await db.pipeline() .collection("books") .select([Field("title").notEqual("1984").as("not1984")]) .execute()
Kotlin
Android
val result = db.pipeline() .collection("books") .select(field("title").notEqual("1984").alias("not1984")) .execute()
Java
Android
Task<Pipeline.Snapshot> result = db.pipeline() .collection("books") .select(field("title").notEqual("1984").alias("not1984")) .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client.pipeline() .collection("books") .select(Field.of("title").not_equal("1984").as_("not1984")) .execute() )
Java
Pipeline.Snapshot result = firestore .pipeline() .collection("books") .select(notEqual(field("title"), "1984").as("not1984")) .execute() .get();
CMP
Sintassi:
cmp(x: ANY, y: ANY) -> Int64
Descrizione:
Confronta x e y e restituisce:
1Lsexè maggiore diy.-1Lsexè inferiore ay.0Laltrimenti.
A differenza di altre funzioni di confronto, la funzione cmp(...) funziona su più tipi,
seguendo lo stesso ordine utilizzato nella fase sort(...). Consulta
Ordine dei tipi di valori per scoprire come vengono ordinati i valori nei vari tipi.
Esempi:
x |
y |
cmp(x, y) |
|---|---|---|
| 1L | 1L | 0L |
| 1.0 | 1L | 0L |
| -1.0 | 1L | -1L |
| 42,5 D | "foo" | -1L |
NULL |
NULL |
0L |
NULL |
ABSENT |
0L |
Passaggi successivi
- Consulta la panoramica delle query della pipeline