FirebaseFirestore Framework Reference
WriteBatch
classWriteBatch:NSObjectA write batch is used to perform multiple writes as a single atomic unit.
A WriteBatch object can be acquired by callingFirestore.batch(). It provides methods for adding writes to the write batch. None of the writes will be committed (or visible locally) untilWriteBatch.commit() is called.
Unlike transactions, write batches are persisted offline and therefore are preferable when you don’t need to condition your writes on read data.
Writes to the document referred to by
document. If the document doesn’t yet exist, this method creates it and then sets the data. If the document exists, this method overwrites the document data with the new values.Declaration
Swift
funcsetData(_data:[String:Any],forDocumentdocument:FIRDocumentReference)->WriteBatchParameters
dataA
Dictionarythat contains the fields and data to write to the document.documentA reference to the document whose data should be overwritten.
Return Value
This
WriteBatchinstance. Used for chaining method calls.Writes to the document referred to by
document. If the document doesn’t yet exist, this method creates it and then sets the data. If you passmerge:true, the provided data will be merged into any existing document.Declaration
Swift
funcsetData(_data:[String:Any],forDocumentdocument:FIRDocumentReference,merge:Bool)->WriteBatchParameters
dataA
Dictionarythat contains the fields and data to write to the document.documentA reference to the document whose data should be overwritten.
mergeWhether to merge the provided data into any existing document. If enabled,all omitted fields remain untouched. If your input sets any field to an empty dictionary, anynested field is overwritten.
Return Value
This
WriteBatchinstance. Used for chaining method calls.Writes to the document referred to by
documentand only replace the fields specified undermergeFields. Any field that is not specified inmergeFieldsis ignored and remains untouched. If the document doesn’t yet exist, this method creates it and then sets the data.It is an error to include a field in
mergeFieldsthat does not have a corresponding value in thedatadictionary.Declaration
Swift
funcsetData(_data:[String:Any],forDocumentdocument:FIRDocumentReference,mergeFields:[Any])->WriteBatchParameters
dataA
Dictionarythat contains the fields and data to write to the document.documentA reference to the document whose data should be overwritten.
mergeFieldsAn
Arraythat contains a list ofStringorFieldPathelementsspecifying which fields to merge. Fields can contain dots to reference nested fields withinthe document. If your input sets any field to an empty dictionary, any nested field isoverwritten.Return Value
This
WriteBatchinstance. Used for chaining method calls.Updates fields in the document referred to by
document. If document does not exist, the write batch will fail.Declaration
Swift
funcupdateData(_fields:[AnyHashable:Any],forDocumentdocument:FIRDocumentReference)->WriteBatchParameters
fieldsA
Dictionarycontaining the fields (expressed as anStringorFieldPath) and values with which to update the document.documentA reference to the document whose data should be updated.
Return Value
This
WriteBatchinstance. Used for chaining method calls.Deletes the document referred to by
document.Declaration
Swift
funcdeleteDocument(_document:FIRDocumentReference)->WriteBatchParameters
documentA reference to the document that should be deleted.
Return Value
This
WriteBatchinstance. Used for chaining method calls.Commits all of the writes in this write batch as a single atomic unit.
Declaration
Swift
funccommit()Commits all of the writes in this write batch as a single atomic unit.
Declaration
Swift
funccommit()asyncthrowsParameters
completionA block to be called once all of the writes in the batch have been successfully written to the backend as an atomic unit. This block will only execute when the client is online and the commit has completed against the server. The completion handler will not be called when the device is offline, though local changes will be visible immediately.
Encodes an instance of
Encodableand overwrites the encoded datato the document referred bydoc. If no document exists,it is created. If a document already exists, it is overwritten.See
Firestore.Encoderfor more details about the encoding process.Declaration
Swift
@discardableResultfuncsetData<T:Encodable>(fromvalue:T,forDocumentdoc:DocumentReference,encoder:Firestore.Encoder=Firestore.Encoder())throws->WriteBatchParameters
valueAn instance of
Encodableto be encoded to a document.encoderThe encoder instance to use to run the encoding.
docThe document to create/overwrite the encoded data to.
Return Value
This instance of
WriteBatch. Used for chaining method calls.Encodes an instance of
Encodableand overwrites the encoded datato the document referred bydoc. If no document exists,it is created. If a document already exists, it is overwritten. If you passmerge:true, the providedEncodablewill be merged into any existing document.See
Firestore.Encoderfor more details about the encoding process.Declaration
Swift
@discardableResultfuncsetData<T:Encodable>(fromvalue:T,forDocumentdoc:DocumentReference,merge:Bool,encoder:Firestore.Encoder=Firestore.Encoder())throws->WriteBatchParameters
valueAn instance of
Encodableto be encoded to a document.docThe document to create/overwrite the encoded data to.
mergeWhether to merge the provided
Encodableinto any existing document.encoderThe encoder instance to use to run the encoding.
Return Value
This instance of
WriteBatch. Used for chaining method calls.Encodes an instance of
Encodableand writes the encoded data to the document referredbydocby only replacing the fields specified undermergeFields.Any field that is not specified in mergeFields is ignored and remains untouched. If thedocument doesn’t yet exist, this method creates it and then sets the data.It is an error to include a field in
mergeFieldsthat does not have a correspondingfield in theEncodable.See
Firestore.Encoderfor more details about the encoding process.Declaration
Swift
@discardableResultfuncsetData<T:Encodable>(fromvalue:T,forDocumentdoc:DocumentReference,mergeFields:[Any],encoder:Firestore.Encoder=Firestore.Encoder())throws->WriteBatchParameters
valueAn instance of
Encodableto be encoded to a document.docThe document to create/overwrite the encoded data to.
mergeFieldsArray of
StringorFieldPathelements specifying which fields to merge. Fields can contain dots to reference nested fields within the document.encoderThe encoder instance to use to run the encoding.
Return Value
This instance of
WriteBatch. Used for chaining method calls.
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Last updated 2025-03-11 UTC.