Firebase.Firestore.Query

A query which you can read or listen to.

Summary

You can also construct refinedQuery objects by adding filters, ordering, and other constraints.

CollectionReference derives from this class as a "return-all" query against the collection it refers to.

Inheritance

Direct Known Subclasses:Firebase.Firestore.CollectionReference

Properties

Count
Returns a query that counts the documents in the result set of this query.
Firestore
The CloudFirestore instance associated with this query.

Public functions

EndAt(DocumentSnapshot snapshot)
Creates and returns a newQuery that ends at the provided document (inclusive).
EndAt(params object[] fieldValues)
Creates and returns a newQuery that ends at the provided fields relative to the order of the query.
EndBefore(DocumentSnapshot snapshot)
Creates and returns a newQuery that ends before the provided document (exclusive).
EndBefore(params object[] fieldValues)
Creates and returns a newQuery that ends before the provided fields relative to the order of the query.
Equals(object obj)
override bool
Equals(Query other)
bool
GetHashCode()
override int
GetSnapshotAsync(Source source)
Asynchronously executes the query and returns all matching documents as aQuerySnapshot.
Limit(int limit)
Creates and returns a newQuery that only returns the last matching documents up to the specified number.
LimitToLast(int limit)
Creates and returns a newQuery that only returns the last matching documents up to the specified number.
Listen(Action<QuerySnapshot > callback)
Starts listening to changes to the query results described by thisQuery.
Listen(MetadataChanges metadataChanges, Action<QuerySnapshot > callback)
Starts listening to changes to the query results described by thisQuery.
OrderBy(string fieldPath)
Creates and returns a newQuery that's additionally sorted by the specified field.
OrderBy(FieldPath fieldPath)
Creates and returns a newQuery that's additionally sorted by the specified field.
OrderByDescending(string fieldPath)
Creates and returns a newQuery that's additionally sorted by the specified field in descending order.
OrderByDescending(FieldPath fieldPath)
Creates and returns a newQuery that's additionally sorted by the specified field in descending order.
StartAfter(DocumentSnapshot snapshot)
Creates and returns a newQuery that starts after the provided document (exclusive).
StartAfter(params object[] fieldValues)
Creates and returns a newQuery that starts after the provided fields relative to the order of the query.
StartAt(DocumentSnapshot snapshot)
Creates and returns a newQuery that starts at the provided document (inclusive).
StartAt(params object[] fieldValues)
Creates and returns a newQuery that starts at the provided fields relative to the order of the query.
Where(Filter filter)
Creates and returns a newQuery with the additional filter.
WhereArrayContains(FieldPath fieldPath, object value)
Creates and returns a newQuery with the additional filter that documents must contain the specified field, the value must be an array, and that the array must contain the provided value.
WhereArrayContains(string fieldPath, object value)
Creates and returns a newQuery with the additional filter that documents must contain the specified field, the value must be an array, and that the array must contain the provided value.
WhereArrayContainsAny(FieldPath fieldPath, IEnumerable< object > values)
Creates and returns a newQuery with the additional filter that documents must contain the specified field, the value must be an array, and that the array must contain at least one value from the provided list.
WhereArrayContainsAny(string fieldPath, IEnumerable< object > values)
Creates and returns a newQuery with the additional filter that documents must contain the specified field, the value must be an array, and that the array must contain at least one value from the provided list.
WhereEqualTo(string fieldPath, object value)
Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value should be equal to the specified value.
WhereEqualTo(FieldPath fieldPath, object value)
Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value should be equal to the specified value.
WhereGreaterThan(string fieldPath, object value)
Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value should be greater than the specified value.
WhereGreaterThan(FieldPath fieldPath, object value)
Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value should be greater than the specified value.
WhereGreaterThanOrEqualTo(string fieldPath, object value)
Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value should be greater than or equal to the specified value.
WhereGreaterThanOrEqualTo(FieldPath fieldPath, object value)
Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value should be greater than or equal to the specified value.
WhereIn(FieldPath fieldPath, IEnumerable< object > values)
Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value must equal one of the values from the provided list.
WhereIn(string fieldPath, IEnumerable< object > values)
Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value must equal one of the values from the provided list.
WhereLessThan(string fieldPath, object value)
Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value should be less than the specified value.
WhereLessThan(FieldPath fieldPath, object value)
Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value should be less than the specified value.
WhereLessThanOrEqualTo(string fieldPath, object value)
Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value should be less than or equal to the specified value.
WhereLessThanOrEqualTo(FieldPath fieldPath, object value)
Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value should be less than or equal to the specified value.
WhereNotEqualTo(string fieldPath, object value)
Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value should not equal the specified value.
WhereNotEqualTo(FieldPath fieldPath, object value)
Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value should not equal the specified value.
WhereNotIn(FieldPath fieldPath, IEnumerable< object > values)
Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value must not equal any value from the provided list.
WhereNotIn(string fieldPath, IEnumerable< object > values)
Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value must not equal any value from the provided list.

Properties

Count

AggregateQueryCount

Returns a query that counts the documents in the result set of this query.

The returned query, when executed, counts the documents in the result set of this query without actually downloading the documents.

Using the returned query to count the documents is efficient because only the final count, not the documents' data, is downloaded. The returned query can count the documents in cases where the result set is prohibitively large to download entirely (thousands of documents).

Details
Returns
An aggregate query that counts the documents in the result set of this query.

Firestore

FirebaseFirestoreFirestore

The CloudFirestore instance associated with this query.

Public functions

EndAt

QueryEndAt(DocumentSnapshotsnapshot)

Creates and returns a newQuery that ends at the provided document (inclusive).

The end position is relative to the order of the query. The document must contain all of the fields provided in the order-by clauses of the query.

This call replaces any previously specified end position in the query.

Details
Parameters
snapshot
The snapshot of the document to end at.
Returns
A new query based on the current one, but with the specified end position.

EndAt

QueryEndAt(paramsobject[]fieldValues)

Creates and returns a newQuery that ends at the provided fields relative to the order of the query.

The order of the field values must match the order of the order-by clauses of the query.

This call replaces any previously specified end position in the query.

Details
Parameters
fieldValues
The field values. ThefieldValues array must not benull or empty (though elements of the array may be), or have more values than query has orderings.
Returns
A new query based on the current one, but with the specified end position.

EndBefore

QueryEndBefore(DocumentSnapshotsnapshot)

Creates and returns a newQuery that ends before the provided document (exclusive).

The end position is relative to the order of the query. The document must contain all of the fields provided in the order-by clauses of the query.

This call replaces any previously specified end position in the query.

Details
Parameters
snapshot
The snapshot of the document to end before.
Returns
A new query based on the current one, but with the specified end position.

EndBefore

QueryEndBefore(paramsobject[]fieldValues)

Creates and returns a newQuery that ends before the provided fields relative to the order of the query.

The order of the field values must match the order of the order-by clauses of the query.

This call replaces any previously specified end position in the query.

Details
Parameters
fieldValues
The field values. ThefieldValues array must not benull or empty (though elements of the array may be), or have more values than query has orderings.
Returns
A new query based on the current one, but with the specified end position.

Equals

overrideboolEquals(objectobj)

Equals

boolEquals(Queryother)

GetHashCode

overrideintGetHashCode()

GetSnapshotAsync

Task<QuerySnapshot>GetSnapshotAsync(Sourcesource)

Asynchronously executes the query and returns all matching documents as aQuerySnapshot.

By default,GetSnapshotAsync attempts to provide up-to-date data when possible by waiting for data from the server, but it may return cached data or fail if you are offline and the server cannot be reached. This behavior can be altered via thesource parameter.

Details
Parameters
source
indicates whether the results should be fetched from the cache only (Source.Cache), the server only (Source.Server), or to attempt the server and fall back to the cache (Source.Default).
Returns
A snapshot of documents matching the query.

Limit

QueryLimit(intlimit)

Creates and returns a newQuery that only returns the last matching documents up to the specified number.

This call replaces any previously-specified limit in the query.

Details
Parameters
limit
The maximum number of items to return. Must be greater than 0.
Returns
A new query based on the current one, but with the specified limit applied.

LimitToLast

QueryLimitToLast(intlimit)

Creates and returns a newQuery that only returns the last matching documents up to the specified number.

You must specify at least oneOrderBy clause forLimitToLast queries, otherwise an exception will be thrown during execution.

This call replaces any previously-specified limit in the query.

Details
Parameters
limit
The maximum number of items to return. Must be greater than 0.
Returns
A new query based on the current one, but with the specified limit applied.

Listen

ListenerRegistrationListen(Action<QuerySnapshot>callback)

Starts listening to changes to the query results described by thisQuery.

Details
Parameters
callback
The callback to invoke each time the query results change. Must not benull. The callback will be invoked on the main thread.
Returns
AListenerRegistration which may be used to stop listening gracefully.

Listen

ListenerRegistrationListen(MetadataChangesmetadataChanges,Action<QuerySnapshot>callback)

Starts listening to changes to the query results described by thisQuery.

Details
Parameters
metadataChanges
Indicates whether metadata-only changes (i.e. onlyQuerySnapshot.Metadata changed) should trigger snapshot events.
callback
The callback to invoke each time the query results change. Must not benull. The callback will be invoked on the main thread.
Returns
AListenerRegistration which may be used to stop listening gracefully.

OrderBy

QueryOrderBy(stringfieldPath)

Creates and returns a newQuery that's additionally sorted by the specified field.

Unlike OrderBy in LINQ, this call makes each additional ordering subordinate to the preceding ones. This means thatquery.OrderBy("foo").OrderBy("bar") in CloudFirestore is similar toquery.OrderBy(x => x.Foo).ThenBy(x => x.Bar) in LINQ.

This method cannot be called after a start/end cursor has been specified withStartAt(DocumentSnapshot),StartAfter(DocumentSnapshot),EndAt(DocumentSnapshot) orEndBefore(DocumentSnapshot) or other overloads.

Details
Parameters
fieldPath
The dot-separated field path to order by. Must not benull or empty.
Returns
A new query based on the current one, but with the additional specified ordering applied.

OrderBy

QueryOrderBy(FieldPathfieldPath)

Creates and returns a newQuery that's additionally sorted by the specified field.

Unlike OrderBy in LINQ, this call makes each additional ordering subordinate to the preceding ones. This means thatquery.OrderBy("foo").OrderBy("bar") in CloudFirestore is similar toquery.OrderBy(x => x.Foo).ThenBy(x => x.Bar) in LINQ.

This method cannot be called after a start/end cursor has been specified withStartAt(DocumentSnapshot),StartAfter(DocumentSnapshot),EndAt(DocumentSnapshot) orEndBefore(DocumentSnapshot) or other overloads.

Details
Parameters
fieldPath
The field path to order by. Must not benull.
Returns
A new query based on the current one, but with the additional specified ordering applied.

OrderByDescending

QueryOrderByDescending(stringfieldPath)

Creates and returns a newQuery that's additionally sorted by the specified field in descending order.

Unlike OrderByDescending in LINQ, this call makes each additional ordering subordinate to the preceding ones. This means thatquery.OrderByDescending("foo").OrderByDescending("bar") in CloudFirestore is similar toquery.OrderByDescending(x => x.Foo).ThenByDescending(x => x.Bar) in LINQ.

This method cannot be called after a start/end cursor has been specified withStartAt(DocumentSnapshot),StartAfter(DocumentSnapshot),EndAt(DocumentSnapshot) orEndBefore(DocumentSnapshot) or other overloads.

Details
Parameters
fieldPath
The dot-separated field path to order by. Must not benull or empty.
Returns
A new query based on the current one, but with the additional specified ordering applied.

OrderByDescending

QueryOrderByDescending(FieldPathfieldPath)

Creates and returns a newQuery that's additionally sorted by the specified field in descending order.

Unlike OrderByDescending in LINQ, this call makes each additional ordering subordinate to the preceding ones. This means thatquery.OrderByDescending("foo").OrderByDescending("bar") in CloudFirestore is similar toquery.OrderByDescending(x => x.Foo).ThenByDescending(x => x.Bar) in LINQ.

This method cannot be called after a start/end cursor has been specified withStartAt(DocumentSnapshot),StartAfter(DocumentSnapshot),EndAt(DocumentSnapshot) orEndBefore(DocumentSnapshot) or other overloads.

Details
Parameters
fieldPath
The field path to order by. Must not benull.
Returns
A new query based on the current one, but with the additional specified ordering applied.

StartAfter

QueryStartAfter(DocumentSnapshotsnapshot)

Creates and returns a newQuery that starts after the provided document (exclusive).

The starting position is relative to the order of the query. The document must contain all of the fields provided in the order-by clauses of the query.

This call replaces any previously specified start position in the query.

Details
Parameters
snapshot
The snapshot of the document to start after.
Returns
A new query based on the current one, but with the specified start position.

StartAfter

QueryStartAfter(paramsobject[]fieldValues)

Creates and returns a newQuery that starts after the provided fields relative to the order of the query.

The order of the field values must match the order of the order-by clauses of the query.

This call replaces any previously specified start position in the query.

Details
Parameters
fieldValues
The field values. ThefieldValues array must not benull or empty (though elements of the array may be), or have more values than query has orderings.
Returns
A new query based on the current one, but with the specified start position.

StartAt

QueryStartAt(DocumentSnapshotsnapshot)

Creates and returns a newQuery that starts at the provided document (inclusive).

The starting position is relative to the order of the query. The document must contain all of the fields provided in order-by clauses of the query.

This call replaces any previously specified start position in the query.

Details
Parameters
snapshot
The snapshot of the document to start at.
Returns
A new query based on the current one, but with the specified start position.

StartAt

QueryStartAt(paramsobject[]fieldValues)

Creates and returns a newQuery that starts at the provided fields relative to the order of the query.

The order of the field values must match the order of the order-by clauses of the query.

This call replaces any previously specified start position in the query.

Details
Parameters
fieldValues
The field values. ThefieldValues array must not benull or empty (though elements of the array may be), or have more values than query has orderings.
Returns
A new query based on the current one, but with the specified start position.

Where

QueryWhere(Filterfilter)

Creates and returns a newQuery with the additional filter.

Details
Parameters
filter
The new filter to apply to the existing query.
Returns
The createdQuery.

WhereArrayContains

QueryWhereArrayContains(FieldPathfieldPath,objectvalue)

Creates and returns a newQuery with the additional filter that documents must contain the specified field, the value must be an array, and that the array must contain the provided value.

AQuery can have only oneWhereArrayContains() filter and it cannot be combined withWhereArrayContainsAny().

Details
Parameters
fieldPath
The name of the fields containing an array to search
value
The value that must be contained in the array.
Returns
A new query based on the current one, but with the additional filter applied.

WhereArrayContains

QueryWhereArrayContains(stringfieldPath,objectvalue)

Creates and returns a newQuery with the additional filter that documents must contain the specified field, the value must be an array, and that the array must contain the provided value.

AQuery can have only oneWhereArrayContains() filter and it cannot be combined withWhereArrayContainsAny().

Details
Parameters
fieldPath
The dot-separated field path to filter on. Must not benull or empty.
value
The value that must be contained in the array.
Returns
A new query based on the current one, but with the additional filter applied.

WhereArrayContainsAny

QueryWhereArrayContainsAny(FieldPathfieldPath,IEnumerable<object>values)

Creates and returns a newQuery with the additional filter that documents must contain the specified field, the value must be an array, and that the array must contain at least one value from the provided list.

AQuery can have only oneWhereArrayContainsAny() filter and it cannot be combined withWhereArrayContains() orWhereIn().

Details
Parameters
fieldPath
The name of the fields containing an array to search.
values
The list that contains the values to match.
Returns
A new query based on the current one, but with the additional filter applied.

WhereArrayContainsAny

QueryWhereArrayContainsAny(stringfieldPath,IEnumerable<object>values)

Creates and returns a newQuery with the additional filter that documents must contain the specified field, the value must be an array, and that the array must contain at least one value from the provided list.

AQuery can have only oneWhereArrayContainsAny() filter and it cannot be combined withWhereArrayContains() orWhereIn().

Details
Parameters
fieldPath
The dot-separated field path to filter on. Must not benull or empty.
values
The list that contains the values to match.
Returns
A new query based on the current one, but with the additional filter applied.

WhereEqualTo

QueryWhereEqualTo(stringfieldPath,objectvalue)

Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value should be equal to the specified value.

Details
Parameters
fieldPath
The dot-separated field path to filter on. Must not benull or empty.
value
The value to compare in the filter.
Returns
A new query based on the current one, but with the additional filter applied.

WhereEqualTo

QueryWhereEqualTo(FieldPathfieldPath,objectvalue)

Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value should be equal to the specified value.

Details
Parameters
fieldPath
The field path to filter on. Must not benull.
value
The value to compare in the filter.
Returns
A new query based on the current one, but with the additional filter applied.

WhereGreaterThan

QueryWhereGreaterThan(stringfieldPath,objectvalue)

Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value should be greater than the specified value.

Details
Parameters
fieldPath
The dot-separated field path to filter on. Must not benull or empty.
value
The value to compare in the filter.
Returns
A new query based on the current one, but with the additional filter applied.

WhereGreaterThan

QueryWhereGreaterThan(FieldPathfieldPath,objectvalue)

Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value should be greater than the specified value.

Details
Parameters
fieldPath
The field path to filter on. Must not benull.
value
The value to compare in the filter.
Returns
A new query based on the current one, but with the additional filter applied.

WhereGreaterThanOrEqualTo

QueryWhereGreaterThanOrEqualTo(stringfieldPath,objectvalue)

Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value should be greater than or equal to the specified value.

Details
Parameters
fieldPath
The dot-separated field path to filter on. Must not benull or empty.
value
The value to compare in the filter.
Returns
A new query based on the current one, but with the additional filter applied.

WhereGreaterThanOrEqualTo

QueryWhereGreaterThanOrEqualTo(FieldPathfieldPath,objectvalue)

Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value should be greater than or equal to the specified value.

Details
Parameters
fieldPath
The field path to filter on. Must not benull.
value
The value to compare in the filter.
Returns
A new query based on the current one, but with the additional filter applied.

WhereIn

QueryWhereIn(FieldPathfieldPath,IEnumerable<object>values)

Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value must equal one of the values from the provided list.

AQuery can have only oneWhereIn() filter and it cannot be combined withWhereArrayContainsAny().

Details
Parameters
fieldPath
The name of the fields containing an array to search.
values
The list that contains the values to match.
Returns
A new query based on the current one, but with the additional filter applied.

WhereIn

QueryWhereIn(stringfieldPath,IEnumerable<object>values)

Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value must equal one of the values from the provided list.

AQuery can have only oneWhereIn() filter and it cannot be combined withWhereArrayContainsAny().

Details
Parameters
fieldPath
The dot-separated field path to filter on. Must not benull or empty.
values
The list that contains the values to match.
Returns
A new query based on the current one, but with the additional filter applied.

WhereLessThan

QueryWhereLessThan(stringfieldPath,objectvalue)

Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value should be less than the specified value.

Details
Parameters
fieldPath
The dot-separated field path to filter on. Must not benull or empty.
value
The value to compare in the filter.
Returns
A new query based on the current one, but with the additional filter applied.

WhereLessThan

QueryWhereLessThan(FieldPathfieldPath,objectvalue)

Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value should be less than the specified value.

Details
Parameters
fieldPath
The field path to filter on. Must not benull.
value
The value to compare in the filter.
Returns
A new query based on the current one, but with the additional filter applied.

WhereLessThanOrEqualTo

QueryWhereLessThanOrEqualTo(stringfieldPath,objectvalue)

Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value should be less than or equal to the specified value.

Details
Parameters
fieldPath
The dot-separated field path to filter on. Must not benull or empty.
value
The value to compare in the filter.
Returns
A new query based on the current one, but with the additional filter applied.

WhereLessThanOrEqualTo

QueryWhereLessThanOrEqualTo(FieldPathfieldPath,objectvalue)

Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value should be less than or equal to the specified value.

Details
Parameters
fieldPath
The field path to filter on. Must not benull.
value
The value to compare in the filter.
Returns
A new query based on the current one, but with the additional filter applied.

WhereNotEqualTo

QueryWhereNotEqualTo(stringfieldPath,objectvalue)

Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value should not equal the specified value.

AQuery can have only oneWhereNotEqualTo() filter, and it cannot be combined withWhereNotIn().

Details
Parameters
fieldPath
The dot-separated field path to filter on. Must not benull or empty.
value
The value to compare in the filter.
Returns
A new query based on the current one, but with the additional filter applied.

WhereNotEqualTo

QueryWhereNotEqualTo(FieldPathfieldPath,objectvalue)

Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value should not equal the specified value.

AQuery can have only oneWhereNotEqualTo() filter, and it cannot be combined withWhereNotIn().

Details
Parameters
fieldPath
The field path to filter on. Must not benull.
value
The value to compare in the filter.
Returns
A new query based on the current one, but with the additional filter applied.

WhereNotIn

QueryWhereNotIn(FieldPathfieldPath,IEnumerable<object>values)

Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value must not equal any value from the provided list.

One special case is thatWhereNotIn cannot match null values. To query for documents where a field exists and is null, useWhereNotEqualTo, which can handle this special case.

AQuery can have only oneWhereNotIn() filter, and it cannot be combined withWhereArrayContains(),WhereArrayContainsAny(),WhereIn(), orWhereNotEqualTo().

Details
Parameters
fieldPath
The name of the fields containing an array to search.
values
The list that contains the values to match.
Returns
A new query based on the current one, but with the additional filter applied.

WhereNotIn

QueryWhereNotIn(stringfieldPath,IEnumerable<object>values)

Creates and returns a newQuery with the additional filter that documents must contain the specified field and the value must not equal any value from the provided list.

One special case is thatWhereNotIn cannot match null values. To query for documents where a field exists and is null, useWhereNotEqualTo, which can handle this special case.

AQuery can have only oneWhereNotIn() filter, and it cannot be combined withWhereArrayContains(),WhereArrayContainsAny(),WhereIn(), orWhereNotEqualTo().

Details
Parameters
fieldPath
The name of the fields containing an array to search.
values
The list that contains the values to match.
Returns
A new query based on the current one, but with the additional filter applied.

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Last updated 2024-02-13 UTC.