Processing mutations for a remote database

A system comprising:

• one or more data processing apparatus;
• and
• a data store storing instructions that, when executed by the one or more data processing apparatus, cause the one or more data processing apparatus to perform operations comprising:
• receiving, from a client device, a request for updates to a client version of a database stored on the client device, the client version of the database corresponding to a version of the database that is locally stored on the client device and locally mutable by the client device independent of other versions of the database, the request including i) a client database version number for the client version of the database and ii) a first cursor specifying a first logical position that indicates a particular database entity included in the client version of the database as a starting point for an update;
• accessing a remote version of the database that is remote from the client device, the remote version of the database including a plurality of database entities, each database entity having a remote entity version that is assigned to the database entity in a monotonically increasing manner between the plurality of database entities for the database each time any database entity is updated in the database;
• for each respective database entity of a plurality of the database entities included in an ordered subset of database entities that begins with a database entity that matches the particular database entity indicated by the first cursor:
• determining, based on a comparison of a remote entity version number of the respective database entity and the client database version number, whether the respective database entity has been updated;
• and
• when the respective database entity has been updated, providing an entity update to the client device that includes the remote entity version number of the respective database entity;
• and
• providing to the client device for updating the client version of the database:
• a remote database version number with at least one provided entity update, the remote database version number equal to a highest remote entity version number from among all the database entities in the remote version of the database and being higher than the remote entity version number included with each provided entity update;
• and
• a second cursor specifying a second logical position that indicates a second particular database entity included in the client version of the database as a subsequent starting position for a subsequent update.

A non-transitory computer readable medium storing instructions that, when executed by one or more data processing apparatus, cause the one or more data processing apparatus to perform operations comprising:

• receiving, from a client device, a request for updates to a client version of a database stored on the client device, the client version of the database corresponding to a version of the database that is locally stored on the client device and locally mutable by the client device independent of other versions of the database, the request including i) a client database version number for the client version of the database and ii) a first cursor specifying a first logical position that indicates a particular database entity included in the client version of the database as a starting point for an update;
• accessing a remote version of the database that is remote from the client device, the remote version of the database including a plurality of database entities, each database entity having a remote entity version that is assigned to the database entity in a monotonically increasing manner between the plurality of database entities for the database each time any database entity is updated in the database;
• for each respective database entity of a plurality of the database entities included in an ordered subset of database entities that begins with a database entity that matches the particular database entity indicated by the first cursor:
• determining, based on a comparison of a remote entity version number of the respective database entity and the client database version number, whether the respective database entity has been updated;
• and
• when the respective database entity has been updated, providing an entity update to the client device that includes the remote entity version number of the respective database entity;
• and
• providing to the client device for updating the client version of the database:
• a remote database version number to the client device with at least one provided entity update, the remote database version number equal to a highest remote entity version number from among all the database entities in the remote version of the database and being higher than the remote entity version number included with each provided entity update;
• and
• a second cursor specifying a second logical position that indicates a second particular database entity included in the client version of the database as a subsequent starting position for a subsequent update.