FIRWriteBatch
@interface FIRWriteBatch : NSObjectA write batch is used to perform multiple writes as a single atomic unit.
A WriteBatch object can be acquired by calling Firestore.batch(). It provides methods for
adding writes to the write batch. None of the writes will be committed (or visible locally)
until WriteBatch.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
Objective-C
- (nonnull FIRWriteBatch *)setData:(nonnull NSDictionary<NSString *, id> *)data forDocument:(nonnull FIRDocumentReference *)document;Parameters
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
Objective-C
- (nonnull FIRWriteBatch *)setData:(nonnull NSDictionary<NSString *, id> *)data forDocument:(nonnull FIRDocumentReference *)document merge:(BOOL)merge;Parameters
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, any nested 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
Objective-C
- (nonnull FIRWriteBatch *)setData:(nonnull NSDictionary<NSString *, id> *)data forDocument:(nonnull FIRDocumentReference *)document mergeFields:(nonnull NSArray<id> *)mergeFields;Parameters
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 ofStringorFieldPathelements specifying which fields to merge. Fields can contain dots to reference nested fields within the document. If your input sets any field to an empty dictionary, any nested field is overwritten.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
Objective-C
- (nonnull FIRWriteBatch *)updateData:(nonnull NSDictionary<id, id> *)fields forDocument:(nonnull FIRDocumentReference *)document;Parameters
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
Objective-C
- (nonnull FIRWriteBatch *)deleteDocument: (nonnull FIRDocumentReference *)document;Parameters
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
Objective-C
- (void)commit; -
Commits all of the writes in this write batch as a single atomic unit.
Declaration
Objective-C
- (void)commitWithCompletion:(nullable void (^)(NSError *_Nullable))completion;Parameters
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.