ditto::ScopedWriteTransaction Class Reference

ScopedWriteTransaction exposes functionality that allows you to perform multiple operations on the store within a single write transaction. More...

Public Member Functions
DocumentId	insert (nlohmann::json content, DocumentId id=DocumentId(), bool is_default=false)
	Inserts a document into the scoped collection and returns the document's ID. More...
DocumentId	insert_with_strategy (nlohmann::json content, DocumentId id=DocumentId(), WriteStrategy write_strategy=WriteStrategy::overwrite)
	Inserts a document into the scoped collection and returns the document's ID. More...
WriteTransactionPendingIDSpecificOperation	find_by_id (DocumentId id) const
	Generates a WriteTransactionPendingIDSpecificOperation with the provided document ID that can be used to update, remove, or evict the document. More...
WriteTransactionPendingCursorOperation	find_all ()
	Generates a WriteTransactionPendingCursorOperation that can be used to update, remove or evict documents. More...
WriteTransactionPendingCursorOperation	find (std::string query)
	Generates a WriteTransactionPendingCursorOperation with the provided query that can be used to update, remove, or evict documents. More...
WriteTransactionPendingCursorOperation	find (std::string query, nlohmann::json query_args)
	Generates a WriteTransactionPendingCursorOperation with the provided query that can be used to update, remove, or evict documents. More...

Public Attributes
std::string	collection_name

Detailed Description

ScopedWriteTransaction exposes functionality that allows you to perform multiple operations on the store within a single write transaction.

Member Function Documentation

find() [1/2]

WriteTransactionPendingCursorOperation ditto::ScopedWriteTransaction::find

(

std::string

query

)

Generates a WriteTransactionPendingCursorOperation with the provided query that can be used to update, remove, or evict documents.

Parameters

query

the query to run against the collection.

Returns

a WriteTransactionPendingCursorOperation that you can use to chain further query-related function calls.

find() [2/2]

WriteTransactionPendingCursorOperation ditto::ScopedWriteTransaction::find	(	std::string	query,
		nlohmann::json	query_args
	)

Generates a WriteTransactionPendingCursorOperation with the provided query that can be used to update, remove, or evict documents.

This is the recommended function to use when performing queries on a collection if you have any dynamic data included in the query string. It allows you to provide a query string with placeholders, in the form of $args.my_arg_name, along with an accompanying dictionary of arguments, in the form of { "my_arg_name": "some value" }, and the placeholders will be appropriately replaced by the matching provided arguments from the dictionary. This includes handling things like wrapping strings in quotation marks and arrays in square brackets, for example.

Parameters

query	the query to run against the collection.
query_args	the arguments to use to replace placeholders in the provided query.

Returns

a WriteTransactionPendingCursorOperation that you can use to chain further query-related function calls.

find_all()

WriteTransactionPendingCursorOperation ditto::ScopedWriteTransaction::find_all

(

)

Generates a WriteTransactionPendingCursorOperation that can be used to update, remove or evict documents.

Returns

a WriteTransactionPendingCursorOperation that you can use to chain further query-related function calls.

find_by_id()

WriteTransactionPendingIDSpecificOperation ditto::ScopedWriteTransaction::find_by_id

(

DocumentId

id

)

const

Generates a WriteTransactionPendingIDSpecificOperation with the provided document ID that can be used to update, remove, or evict the document.

Parameters

id	the ID of the document.

Returns

a WriteTransactionPendingIDSpecificOperation that you can chain function calls to either get the document immediately or get updates about it over time.

insert()

DocumentId ditto::ScopedWriteTransaction::insert	(	nlohmann::json	content,
		DocumentId	id = DocumentId(),
		bool	is_default = false
	)

Inserts a document into the scoped collection and returns the document's ID.

Parameters

[in]	content	the value to insert into the collection.
[in]	id	the ID to use for the document. If no ID is provided (or a DocumentId constructed using the default DocumentId constructor is used) then Ditto will automatically assign an ID.
[in]	is_default	represents whether or not the data being inserted should be treated as default data or not. Set this to true if you want to set a default value that you expect to be overwritten by other devices in the network. The default value is false.

Returns

the ID of the inserted document.

insert_with_strategy()

DocumentId ditto::ScopedWriteTransaction::insert_with_strategy	(	nlohmann::json	content,
		DocumentId	id = DocumentId(),
		WriteStrategy	write_strategy = WriteStrategy::overwrite
	)

Inserts a document into the scoped collection and returns the document's ID.

Parameters

[in]	content	the value to insert into the collection.
[in]	id	the ID to use for the document. If no ID is provided (or a DocumentId constructed using the default DocumentId constructor is used) then Ditto will automatically assign an ID.
	write_strategy	specifies the desired strategy for inserting a document. The default value is WriteStrategy::overwrite.

Returns

the ID of the inserted document.

Member Data Documentation

collection_name

std::string ditto::ScopedWriteTransaction::collection_name

The name of the collection that the scoped write transaction is scoped to.